JP2002278114A - Method and device for electrophotography - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and a device for electrophotography which establish a toner recycle system by using an a-Si photosensitive body and injection electrostatic charging. SOLUTION: The method and device for electrophotography are equipped with an electrostatic charging means having an image carrier which is constituted by laminating an a-Si photoconductive layer and an a-C surface layer containing at least silicon atoms on a conductive base and characterized by that the silicon atom content rate of the surface layer is 0.2 to 20 atom.% magnetic toner which has toner particle containing at least binding resin and magnetic bodies and inorganic powder and whose means circularity is >=0.950 and whose saturated magnetism under 79.6 kA/m is 10 to 50 Am<2> /kg, electrostatically charged particles made principally of conductive particles having 0.1 to 10 μm particle size, and a conductive and elastic surface and carries the electrostatically charge particles and are characterized by that the electrostatically charged particles come into contact with the image carrier to charge it to the negative polarity, an electrostatic latent image is formed by an IAE system, and there is not cleaning process between transfer and the electrostatic charging.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-single-crystal silicon electrophotographic photosensitive member, a contact charging means, and a spherical toner.
More specifically, the present invention relates to an electrophotographic method and apparatus using a specific system in which there is no cleaning process between transfer and charging. Specifically, a surface layer having a specific silicon atom content (ratio of silicon atoms to the total amount of silicon atoms and carbon atoms) is prepared. The present invention relates to an electrophotographic method and apparatus using an added non-single-crystal silicon photoconductor.

[0002]

2. Description of the Related Art Conventionally, an electrophotographic method generally repeats a cycle of charge-exposure-development-transfer-cleaning of toner remaining after transfer-discharging of residual charge of a photoconductor-charging. In this method, the transfer residual toner remaining on the photoreceptor (image carrier) after transfer is removed from the photoreceptor surface by a cleaner (cleaning device) to become waste toner. It is desirable not to come out. Therefore, the electrophotographic device of the toner recycling process is configured so that the cleaner is eliminated, and the transfer residual toner on the photoreceptor after transfer is removed from the photoreceptor by "development and cleaning" by a developing device and is collected and reused in the developing device. Has also appeared. JP-A-10-307455 discloses such an electrophotographic apparatus.

[0003] Developing and cleaning means that the toner remaining on the photoreceptor after transfer is developed at the next and subsequent steps, that is, the photoreceptor is subsequently charged and exposed to form a latent image. This is a method of recovering by a picking bias (fogging potential difference Vback, which is a potential difference between a DC voltage applied to the developing device and a surface potential of the photoconductor). According to this method, since the transfer residual toner is collected in the developing device and reused after the next process, waste toner can be eliminated, and troublesome maintenance can be reduced. Further, the cleaner-less has a great advantage in terms of space, and the size of the electrophotographic apparatus can be greatly reduced.

Hereinafter, a toner recycling process using a developing / cleaning process will be described with reference to FIG. (1) The photosensitive member 201 is uniformly charged by applying a voltage by the contact charging member 202. In the case of this figure, it is negatively charged. (2) Exposure (for example, laser light) of the reversal development method corresponding to image information on the uniformly negatively charged photoconductor 201
03 to form a latent image. (3) The toner 205, which is a colored powder to which an electric charge is applied from the developing device 204, is supplied to the surface of the photoconductor 201 in a form corresponding to the latent image to form a visible image. In this case, a negatively charged toner is used. (4) The toner image is transferred to the transfer material 207 by a member that applies a voltage by the transfer roller 206 or imparts an electrostatic attraction force, and is fixed by the fixing device 209. At this time, a part of the toner is transferred and remains, and a part of the toner is charged to a polarity opposite to the original polarity by a transfer charging member to which a voltage having a polarity opposite to that of the toner is applied. This is called a reversal toner 208. In this case, the transfer charge is positive. (5) The transfer residual toner remaining on the photoreceptor surface is charged to the same polarity as the charging polarity including the reversal toner by the rubbing between the contact charging member 202 and the photoreceptor 201 to which the voltage of (1) is applied. It is re-applied and discharged again onto the photoreceptor. Aligning the inverted toner to the original polarity is called toner polarity normalization. (6) Toner 20 recharged with charge equal to charge polarity
5 is again collected by the developing device 204 together with the surplus toner during development by the developing bias of the developing device. Such a series of cycles enables a system that does not generate waste toner. The explanation here is only a summary,
It is not limited to this description.

Japanese Patent Application Laid-Open No. Hei 10-307455 discloses a toner recycling process for a non-single-crystal silicon photoreceptor. Japanese Patent Application Laid-Open No. 2000-98846 discloses contact charging of a non-single-crystal silicon photoconductor, particularly a non-single-crystal silicon photoconductor having a surface layer made of non-single-crystal carbon.

Also, in Japanese Patent Publication No. 2811312 and the like,
The value of x in the composition formula Si _1-x C _x is there disclosure 0.5 <x <0.9 technology, in JP-A-10-20663 discloses such, the value of x in the composition formula Si _1-x C _x There is a technical disclosure of 0.95 ≦ x <1.

On the other hand, Japanese Patent Application Laid-Open No. Hei 10-21946 discloses a technique for improving the discharge of toner without using a cleaner by applying a voltage lower than the saturation potential of the photoreceptor to the charging means and using the charging means. JP-A-10-274884
Japanese Patent Application Laid-Open No. 9-325578 discloses that it is better to normalize the toner in the toner recycling process. There is a disclosure regarding a charge applying means other than the original charging.

[0008] Non-single-crystal silicon photoreceptors have unmatched potential stability and are used especially in high-speed copying machines and high-speed printers. In particular, a photoconductor in which a photoconductive layer composed of a non-single-crystal material mainly composed of silicon atoms is laminated on a conductive substrate and a surface layer composed of a non-single-crystal material mainly composed of carbon atoms is non-single-crystal It has excellent properties such as lubrication, high hardness, and oxidation resistance, which are the characteristics of carbon films, such as anti-fusing, long life, and environmental stability.

There has been a great demand for excellent electric potential stability even in the field of small-sized machines and popularized machines, but the number of prints before the main body is rejected is at most one million, and non-single-crystal silicon Due to the mismatch with the durable life of millions of bodies, it is not widely used.

In the cleanerless system described above, in the non-single-crystal silicon photoreceptor, due to the mismatch of the toner and the charging system with the charging member, the reverse toner is removed by the fog removing bias in the step (5). There is a phenomenon that the polarity distribution is difficult to recover, specifically, the average polarity in the direction opposite to the charging polarity is converted, and it is not possible to achieve a cleaner-less system that fully adds the advantages of the non-single-crystal silicon photoconductor There were challenges.

In particular, in a surface layer composed of a non-single-crystal material having a carbon atom as a base, the reversal toner tends to be less normalized than a surface layer composed of an organic substance such as a resin.
This may cause image trouble such as image fogging and low density due to deterioration of the developer.

What is particularly important is that the toner and the photoreceptor have the same charge polarity, that is, image formation by the IAE (Image Area Exposure, meaning "image exposure") method in which the image area is exposed and the potential attenuated part is developed. It is a method. By being charged as described above, the toner mixed in the charger is repelled from the charging member and is discharged onto the photoreceptor, and since the state is a normal state as the toner, the toner is recovered by the developing bias. Is established. Conversely, in the BAE (“back scan exposure”) system in which the non-image area is exposed and the area other than the area where the potential is attenuated is developed, the charging polarity of the toner and that of the photoconductor are different, so that the charging process is sufficient. In some cases, the toner may not be discharged without being discharged, or may not be collected in the developing process even if the discharge is sufficiently charged.

[0013]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned technical problems, and can be widely used in small-sized machines and popular machines even when a non-single-crystal silicon photoconductor is used. It is an object of the present invention to provide an electrophotographic method and an electrophotographic apparatus that make a cleaner-less toner recycling process having a recycling effect function well.

That is, wastes discharged over the lifetime of the electrophotographic apparatus are greatly reduced, no image deletion or image unevenness occurs in various environments, and extremely clear images can be stably obtained for a long period of time. It is an object to provide an electrophotographic apparatus and an electrophotographic method obtained.

Still another object of the present invention is to provide an electrophotographic apparatus and an electrophotographic method capable of stably obtaining high-quality images for a long period of time with a long service life of a charging member and a minimum maintenance cost.

Further, the a-Si photosensitive member is uniformly charged,
An object of the present invention is to provide an electrophotographic apparatus and an electrophotographic method capable of obtaining a clear image with no unevenness, uniform, high contrast, high resolution, and little fog.

[0017]

Means for Solving the Problems In order to solve the above problems, the present inventors have conducted intensive studies on the step (5) for normalizing the reversal toner. This process is extremely smooth and stable by using a non-single-crystal silicon photoreceptor to which a surface layer having a specific silicon atom content (ratio of silicon atoms to the total amount of silicon atoms and carbon) is added. It was found that it was done in a typical way.

More specifically, the image carrier comprises a photoconductive layer composed of a non-single-crystal material having silicon atoms as a base on a conductive substrate and a non-monolayer containing carbon atoms as a base and containing at least silicon atoms. A surface layer made of a crystalline material is laminated, and the silicon atom content (ratio of silicon atoms to the total amount of silicon atoms and carbon) of the surface layer is 0.2 atomic% or more and 20 atomic% or less; The toner is a magnetic toner having toner particles containing at least a binder resin and a magnetic substance and inorganic fine powder, and having an average circularity of 0.950 or more, and 79.6 kA / m of the magnetic toner. (10
00 Oersted) and the saturation magnetization is 10 Am ² /
kg (emu / g) or more and 50 Am ² / kg or less,
The charging means is composed of charged particles mainly composed of conductive particles having a particle size of 0.1 μm to 10 μm, and a charged particle carrier having a surface having conductivity and elasticity and supporting the charged particles. The charged particles are brought into contact with the image carrier, the surface of the image carrier is charged to a negative polarity, an electrostatic latent image is formed by an IAE method in which the potential is attenuated by exposure, and the portion in which the potential is attenuated is a toner. An extremely good toner recycling process was achieved by an electrophotographic method and apparatus characterized in that there was no cleaning step between transfer and electrification.

The present inventors have proposed the above-mentioned image carrier (hereinafter referred to as “a
In addition to pursuing higher image quality in an electrophotographic apparatus using the same (also referred to as “Si photoreceptor”), studies have been made earnestly to significantly reduce waste discharged during the lifetime of the electrophotographic apparatus. As a result, removing the cleaning step to reuse the transfer residual toner and collecting the transfer residual toner in the developing step can suppress the discharge of the transfer residual toner, which is very effective in reducing waste. Came to the conclusion.

However, when the corona charger is used in the charging step, the transfer residual toner passes through the charger so that the transfer residual toner on the a-Si photoreceptor is collected in order to collect the transfer residual toner in the developing step. It was found that the corona discharge unevenness was induced by the influence of the toner to cause charging unevenness, and in the worst case, abnormal discharge occurred to damage the a-Si photosensitive member.

In consideration of the problem of image deletion and uneven charging, which is likely to be a problem when the a-Si photoreceptor is charged by a corona charger, a contact charging type charging unit, which has attracted attention, was examined. Can be prevented, however, when the transfer residual toner passes through the charger, the transfer residual toner contaminates the contact charger, thereby deteriorating the performance of the charging member and shortening the life of the charging member. In some cases, the image contrast and uniformity are deteriorated due to a decrease in charging ability, and further, the transfer residual toner adhered to the contact charger is deteriorated in performance, resulting in a decrease in image quality, for example, an increase in fog.

The present inventors have conducted intensive studies on the optimization of the a-Si photosensitive member and the toner using a contact charging method capable of suppressing abnormal discharge. A non-single-crystal material containing at least hydrogen, carbon atoms as a base material and at least silicon atoms, wherein the surface layer has a silicon atom content (ratio of silicon atoms to the total amount of silicon atoms and carbon) of 0.
The toner is a spherical toner having a content of at least 2 atomic% and not more than 20 atomic%, having toner particles containing at least a binder resin and inorganic fine powder, and having an average circularity of 0.950 or more. Was found to be effective. As a result of examining the situation of the contamination of the contact charging member by the transfer residual toner, even if the charging member is once contaminated with the transfer residual toner, the transfer residual toner on the charging member is quickly discharged onto the a-Si photosensitive member. In addition, it has been found that it is possible to prevent a reduction in the life and charging ability of the charging member by being collected in the developing step. Therefore, as a result of examining a configuration in which the transfer residual toner is easily discharged from the charging member to the a-Si photoconductor, it has been found that it is useful to use the above-described image carrier having the specific surface layer and the specific spherical toner.

Although the details of this mechanism are unknown at present, since the a-Si photoreceptor and the toner have a specific adhesive force, the transfer residual toner present on the charging member can be efficiently a-Si photosensitive. It is presumed that the toner is exhaled to the body. At that time, since the specific surface layer and the spherical toner are effective, the surface free energy of the surface layer of the image carrier and the adhesive force due to the shape of the spherical toner (mainly, It is presumed that the intermolecular force is acting largely, and this adhesive force is based on the silicon atom content of the surface layer (the ratio of silicon atoms to the total amount of silicon atoms and carbon) and the average circularity of the spherical toner. It is considered that it largely depends on.

As described above, the present invention relates to an a-Si photosensitive device having a contact charging device, a specific spherical toner, and a surface layer having a specific silicon atom content (ratio of silicon atoms to the total amount of silicon atoms and carbon). By combining the three members, the body, an electrophotographic apparatus with high image quality, long life, and low waste is made possible.

Hereinafter, the present invention will be described in detail. The image carrier used in the present invention is a conductive substrate, and a photoconductive layer formed of a non-single-crystal material having at least one of hydrogen and halogen and a silicon atom as a base on the conductive substrate, A surface layer composed of a non-single-crystal material containing any one of hydrogen and halogen, carbon atoms as a host, and containing at least silicon atoms, and a silicon atom content of the surface layer (silicon atoms and carbon atoms). (A ratio of silicon atoms to the total amount) is 0.2 atomic% or more and 20 atomic% or less.

FIG. 1 and FIG. 2 are examples of a schematic sectional view of an image carrier used in the present invention. A-Si shown in FIG.
The photoreceptor has a conductive substrate 101 made of aluminum or the like, a charge injection blocking layer (lower blocking layer) 102, a photoconductive layer 103, and a surface layer 105 sequentially laminated on the surface of the conductive substrate 101. Here, the charge injection blocking layer 102 is
This block prevents the injection of electric charges from the photoconductive layer 103 into the photoconductive layer 103, and is provided as necessary. In addition, the photoconductive layer 10
Reference numeral 3 denotes a non-single-crystal material containing at least silicon atoms and exhibits photoconductivity. Further, the photoconductive layer 103
The buffer layer 104 may be provided between the surface layer 105 and the surface layer 105 as a layer capable of preventing charge injection from the surface into the photoconductive layer 103 and / or a layer capable of protecting the surface.

As shown in FIG. 2, the photoconductive layer 103 is composed of a charge transport layer 107 made of a non-single-crystal material containing at least silicon atoms and carbon atoms, and a non-single-crystal material containing at least silicon atoms. The charge generation layer 106 may be of a function-separated type in which the charge generation layers 106 are sequentially stacked. First,
The production outline of the non-single-crystal silicon photoreceptor portion serving as a base will be described.

(Conductive Substrate) The substrate of the conductive substrate may be either conductive or electrically insulating. Examples of the conductive substrate include Al, Cr, Mo, Au, In, and N.
Metals such as b, Te, V, Ti, Pt, Pd, Fe, and alloys thereof, for example, stainless steel. Also, polyester, polyethylene, polycarbonate,
Films or sheets of synthetic resin such as cellulose acetate, polypropylene, polyvinyl chloride, polystyrene, polyamide, etc., electrically insulating supports such as glass, ceramics, etc. Can be used as

(Photoconductive layer) The photoconductive layer is formed by, for example, a glow discharge method (for example, an AC discharge CVD method such as a low frequency CVD method, a high frequency CVD method or a microwave CVD method, or a DC discharge CVD method), a sputtering method, It can be formed by various thin film deposition methods such as a vacuum deposition method, an ion plating method, a photo CVD method, and a thermal CVD method. These thin film deposition methods are appropriately selected and adopted depending on factors such as manufacturing conditions, the degree of load under capital investment, the manufacturing scale, and the characteristics desired for the image carrier for an electrophotographic device to be manufactured. The glow discharge method, particularly the RF band, the μW band, or the VH, is used because it is relatively easy to control the conditions for producing an image carrier for an electrophotographic apparatus having the following characteristics.
The high-frequency glow discharge method using the power frequency in the F band is preferable.

In order to form the photoconductive layer 103 by the glow discharge method, basically, as is well known, silicon atoms (S
At least one of a source gas for supplying Si that can supply i), a source gas for supplying H that can supply hydrogen atoms (H), and a source gas for supplying X that can supply halogen atoms (X) Is introduced in a desired gas state into a reaction vessel in which the pressure can be reduced, a glow discharge is generated in the reaction vessel, the introduced raw material gas is decomposed, and a predetermined gas is installed in a predetermined position in advance. A-S on the conductive substrate 101
i: A layer composed of H and X may be formed.

Further, the dangling bonds of silicon atoms are compensated,
In order to improve the layer quality, in particular, the photoconductivity and the charge retention characteristics, it is necessary that the photoconductive layer 103 contains at least one of a hydrogen atom and a halogen atom. The content of atoms or the sum of hydrogen atoms and halogen atoms is 10 to 30 atom%, more preferably 15 to 25 atom%, based on the sum of silicon atoms, hydrogen atoms and halogen atoms. It is desirable to achieve the above object (compensation of dangling bonds of silicon atoms, etc.).

As the halogen compound which can be suitably used in the present invention, specifically, fluorine gas (F ₂ ), Br
F, ClF, ClF ₃ , BrF ₃ , BrF ₅ , IF ₃ , IF
_And interhalogen compounds such as ₇ . As a silicon compound containing a halogen atom, that is, a silane derivative substituted by a so-called halogen atom, specifically, for example, silicon fluoride such as SiF ₄ or Si ₂ F ₆ can be preferably mentioned.

In the present invention, it is preferable that the photoconductive layer 103 contains atoms for controlling conductivity as necessary. The atoms for controlling the conductivity may be contained in the photoconductive layer 103 in a state of being uniformly distributed in the photoconductive layer 103, or there may be a part containing the atoms in the layer thickness direction in a non-uniform distribution state. Is also good.

Examples of the atoms for controlling the conductivity include so-called impurities in the semiconductor field.
An atom belonging to Group 13 of the periodic table that gives p-type conduction properties (hereinafter abbreviated as “Group 13 atom”) or an atom belonging to Group 15 of the periodic table that gives n-type conduction properties (hereinafter abbreviated as “Group 15 atom”). Do) can be used.

Specific examples of Group 13 atoms include boron (B), aluminum (Al), gallium (Ga), indium (In), and thallium (Tl).
Al and Ga are preferred. Specific examples of Group 15 atoms include phosphorus (P), arsenic (As), antimony (Sb),
There is bismuth (Bi), and P and As are particularly preferable.

It is desirable that the content of the atoms controlling the conductivity contained in the photoconductive layer 103 be appropriately determined in accordance with the charging characteristics, the expected performance of the electrophotographic apparatus, and the like. × 10 ^-2 to 1 × 10 ⁴ atoms p
pm, more preferably 5 × 10 ^{-2 to} 5 × 10 ³ atoms pp
m, most preferably 1 × 10 ^-1 to 1 × 10 ³ atomic ppm.

Atoms that control conductivity, for example, thirteenth
In order to structurally introduce a group 13 atom or a group 15 atom, a source material for introducing a group 13 atom or
The raw material for introducing the group V atom is in a gaseous state, and the photoconductive layer 10
What is necessary is just to introduce into a reaction container with other gas for forming 3. As a raw material for introducing a Group 13 atom or a raw material for introducing a Group 15 atom, a material which is gaseous at ordinary temperature and normal pressure or which can be easily gasified at least under layer forming conditions is employed. It is desirable.

Further, these raw materials for introducing atoms for controlling conductivity may be diluted with H ₂ , He or the like as necessary.

Further, in the present invention, the photoconductive layer 103
It is also effective to make a carbon atom, an oxygen atom, and a nitrogen atom alone or in combination. The content of carbon, oxygen and nitrogen atoms is preferably 1 to the sum of silicon, carbon, oxygen and nitrogen atoms.
× 10 ^-5 to 10 atomic%, more preferably 1 × 10 ^-4 to 8
Atomic%, optimally 1 × 10 ^{−3 to} 5 atomic% is desirable. Carbon atoms, oxygen atoms, and nitrogen atoms may be evenly and uniformly contained in the photoconductive layer, or have a non-uniform distribution such that the content changes in the thickness direction of the photoconductive layer. There may be parts.

In the present invention, the thickness of the photoconductive layer 103 is determined as desired from the viewpoint of obtaining desired electrophotographic characteristics and economic effects, and is preferably 15 to 60 μm, more preferably 20 to 60 μm. It is desirable that the thickness be 50 μm, most preferably 20 to 40 μm. If the thickness is less than 15 μm, the amount of current passing through the charging member increases, and the deterioration tends to be accelerated. When the thickness exceeds 60 μm, the abnormally grown portion of the a-Si photoreceptor becomes large.
0 μm, and 5 to 20 μm in the height direction, the damage to the charging member rubbing the surface may not be ignored.

The thickness of the photoconductive layer 103 can be adjusted according to the film forming conditions such as the amount of the source gas to be introduced, but it can be adjusted with a film thickness meter (for example, HELMUTFISTERGMBH).
It can be measured by using FisherScopes (manufactured by Co., Ltd.), and the thickness of the photoconductive layer 103 can be confirmed.

Further, the temperature of the conductive substrate 101 at the time of depositing the photoconductive layer is appropriately selected in an optimum range according to the layer design.
° C, more preferably 230-330 ° C, optimally 250
It is desirable that the temperature be set to 310 ° C.

(Surface Layer) The image bearing member used in the present invention is a non-single-crystal material (“a-SiC: H (X ) "). The content of silicon atoms contained in the surface layer is 0.2 to 20 atomic% in terms of the ratio of silicon atoms to the sum of carbon atoms and silicon atoms in the surface layer, Si / (Si + C). And

When the content of silicon atoms in the surface layer is 0.2
If the content is less than atomic%, normalization of the toner discharged from the charging unit becomes insufficient, and fog is likely to occur.
When the content of silicon atoms exceeds 20 atomic%, the discharge of the toner from the charging unit is deteriorated, the charging characteristics are deteriorated, and fog is generated and surface wear is easily increased.

A-SiC: H (X) and aC: H
(X) (meaning “non-single-crystal material containing at least one of hydrogen and halogen and having a carbon atom as a base”) has high hardness and excellent durability. AC here: H (X)
The term "mainly" means amorphous carbon having an intermediate property between graphite (diamond) and diamond, but may partially include microcrystals or polycrystals. Surface layer 10 containing a-SiC: H (X) used in the present invention
5 can obtain the same effect even if some impurities are contained. For example, even if the surface layer contains impurities such as N, O, P, and B, the content is 1 to all elements.
The effect of the present invention can be sufficiently obtained if the content is about 0 atomic% or less.

The surface layer used in the present invention preferably contains a hydrogen atom. Inclusion of hydrogen atoms effectively compensates for structural defects in the film and reduces the local level density, thereby improving the transparency of the film and suppressing unwanted unwanted light absorption in the surface layer. This improves light sensitivity. It is said that the presence of hydrogen atoms in the film plays an important role in solid lubricity.

The content of hydrogen atoms contained in the film of the surface layer used in the present invention is preferably 41 to 60 atomic%, more preferably 45 to 50 atomic% in terms of H / (Si + C + H). ing. When the amount of hydrogen is less than 41 atomic%, the optical band gap becomes narrow, which is not suitable in terms of sensitivity. On the other hand, when the content exceeds 60 atomic%, the hardness is reduced, and shaving is likely to occur. Generally, the optical band gap can be suitably used as long as it is about 1.2 eV to 2.2 eV, and more preferably 1.6 eV or more from the viewpoint of sensitivity.

This surface layer has a free surface and is intended to achieve the objects of the present invention such as the effect of preventing abrasion and scratches during long-term use, and the prolongation of the life of the charging member and the stabilization of the charging ability. Is provided.

The thickness of the surface layer is determined by measuring the degree of interference with a reflection spectroscopic interferometer (MCPD2000 manufactured by Otsuka Electronics Co., Ltd.), and calculating the film thickness from this value and a known refractive index. The thickness of the surface layer described later can be adjusted by film formation conditions and the like. The thickness is preferably 5 to 2000 nm, more preferably 10 to 100 nm. When the thickness is less than 5 nm, it is difficult to obtain the effect in long-term use. 20
If the thickness exceeds 00 nm, it is necessary to consider demerits such as a decrease in photosensitivity and residual charge, so that the thickness is preferably 2000 nm or less.

The substrate temperature is adjusted from room temperature to 400 ° C., but if the substrate temperature is too high, the band gap decreases and the transparency decreases, so a lower temperature setting is preferable.

The refractive index of the surface layer is suitably used if it is about 1.6 to 2.8, and preferably 1.6 to 2.8.
2, particularly preferably 1.6 to 2.0. Here, the refractive index is measured by long-wavelength light multiplex interference. Specifically, a sample obtained by forming a surface layer on a glass substrate (7059 manufactured by Coating) is applied to a visible spectroscope (eg, 330 manufactured by Hitachi).
Then, the spectral transmittance is measured from around 2500 nm to the short wavelength side (wavelength range in which 4 to 5 extreme values are found), and the refractive index is calculated using the obtained extreme value wavelength / transmittance. In addition, surface layer 1
The relative dielectric constant of 05 is obtained by squaring the refractive index.

Further, the content of silicon atoms in the surface layer (the ratio of silicon atoms to the total amount of silicon atoms and carbon)
Measures the relative values of silicon atoms and carbon using ESCA (such as "SSX-100" manufactured by SSI, USA)
Obtained by calculating the ratio.

The surface layer 105 is formed, for example, by a glow discharge method.
It can be formed by a known thin film deposition method such as a sputtering method, a vacuum evaporation method, an ion plating method, a photo CVD method, and a thermal CVD method. These thin film deposition methods
It is appropriately selected and adopted depending on factors such as the manufacturing conditions, the load under capital investment, the manufacturing scale, and the characteristics desired for the image carrier for an electrophotographic device to be manufactured. It is preferable to use a deposition method equivalent to that of the conductive layer.

For forming the surface layer, a known method is used in which at least a raw material gas such as a hydrocarbon-based gas is decomposed by plasma and deposited to form a film. More specifically, a plasma CVD method using a high frequency (VHF band) of 50 to 450 MHz or a plasma CVD method using RF power
The VD method can be preferably exemplified.

The high frequency power for decomposing the raw material gas is preferably as high as possible because the decomposition of hydrocarbon proceeds sufficiently. Specifically, the unit time (min) and the standard state ( normal), the amount of electricity (W) per unit volume (ml) of gas is 5 W · mi
n / ml (normal) or more is preferable, but if the temperature is too high, abnormal discharge occurs and the characteristics of the image carrier deteriorate. Therefore, it is necessary to suppress the electric power to such an extent that abnormal discharge does not occur.

The pressure in the discharge space is 1 when using normal RF (typically 13.56 MHz) power.
3.3 Pa to 1333 Pa (0.1 Torr to 10 To)
rr), 13.3 mP to 13.3 Pa (0.1 m) when using the VHF band (typically 50 to 450 MHz).
(Torr to 100 mTorr).

Further, in the present invention, it is preferable that the surface layer 105 contains atoms for controlling conductivity as necessary. The atoms for controlling the conductivity may be contained in the surface layer 105 in a state of being uniformly distributed without unevenness,
Alternatively, there may be a portion contained in a non-uniform distribution state in the layer thickness direction.

Examples of the atoms for controlling the conductivity include so-called impurities in the field of semiconductors, such as atoms belonging to Group 13 of the periodic table giving p-type conduction characteristics or a period giving n-type conduction characteristics. An atom belonging to Group 15 of the Table can be used. In the present invention, the content of atoms for controlling conductivity contained in the surface layer is appropriately determined as desired, but is preferably 1
0 to 1 × 10 ⁴ atomic ppm, more preferably 50 to 5 × 1
0 ³ atomic ppm, optimally 1 × 10 ² to 1 × 10 ³ atomic p
pm.

Further, between the surface layer 105 and the photoconductive layer 103, a region where the content of carbon atoms changes so as to decrease toward the photoconductive layer 103 may be provided. Thereby, the adhesion between the surface layer and the photoconductive layer can be improved, and the influence of interference due to light reflection at the interface can be further reduced.

In the surface layer of the present invention, if necessary,
Atoms may be included. Halogen atom supply gas
Examples of substances that can be_Two, BrF, Cl
F, ClF_Three, BrF_Three, BrF_Five, IF_Three, IF₇Like
Interhalogen compounds can be mentioned. Further CF_Four,
CHF_Three, C_TwoF₆, ClF_Three, CHClF_Two, F_Two, C
_ThreeF ₈, C_FourF_TenA fluorine-containing gas such as
You.

In the case where halogen atoms are contained in the surface layer, it is preferable that the high-frequency power during film formation be as high as possible because decomposition of the source gas proceeds sufficiently. / Min (normal)
However, if the power is too high, abnormal discharge will occur and the characteristics of the electrophotographic photoreceptor will be deteriorated. Therefore, it is necessary to suppress the electric power to such a level that abnormal discharge does not occur.

In the case where halogen atoms are contained in the surface layer, the pressure in the discharge space at the time of film formation is controlled by ordinary RF.
When using power (typically 13.56 MHz), the power is generally 13.3 Pa to 1333 Pa,
A good film can be obtained when the film is manufactured in a range of 33 Pa or less. When a VHF band (typically 50 to 450 MHz) is used, the pressure is generally maintained at about 13.3 mPa to 13.3 Pa, but a pressure as low as possible is desirable.

In the present invention, the content of halogen atoms contained in the surface layer is appropriately determined as desired, but is preferably 6 to 50 atom%, more preferably 30 to 50 atom%, based on all atoms. % Is preferred.

(Buffer Layer) The image carrier used in the present invention comprises a buffer layer 10 between the surface layer and the photoconductive layer.
It is also preferable that the form provided with 4 is provided.

The buffer layer contains at least one of hydrogen and halogen and is based on amorphous silicon (a-Si (H, X)) having silicon atoms as a base,
Further, it is composed of a non-single-crystal material further containing at least one or more atoms selected from carbon atoms, nitrogen atoms and oxygen atoms. Examples of such non-single-crystal materials include amorphous silicon carbide, amorphous silicon nitride, and amorphous silicon oxide containing at least one of hydrogen and halogen. More preferably, amorphous silicon carbide (a-Si: C) having a composition intermediate between a-Si and a | C: H
It is preferably formed of a non-single-crystal material mainly composed of (H, X)).

In this case, from the photoconductive layer 103 to the surface layer 10
It is also possible to continuously change the composition of the buffer layer 104 toward 5, and providing such a buffer layer is effective for preventing interference and the like. In addition, it is also possible to control the conductivity type by adding a dopant such as a group 13 element or a group 15 element to the buffer layer 104 so as to have an upper stopping power for preventing injection of charged carriers from the surface.

As the source gas used for the buffer layer in the present invention, the following can be suitably mentioned.

Examples of the substance that can serve as a carbon supply gas include:
Hydrocarbons in the gaseous state or gasifiable hydrocarbons such as CH ₄ , C ₂ H ₆ , C ₃ H ₈ , and C ₄ H ₁₀ are mentioned to be effectively used.

Substances that can serve as nitrogen or oxygen supply gas include NH ₃ , NO, N ₂ O, NO ₂ , O ₂ , CO, C
Compounds in a gaseous state or gasifiable compounds such as O ₂ and N ₂ are mentioned as being effectively used.

The buffer layer is formed, for example, by a plasma CVD method,
It can be manufactured by a sputtering method or an ion plating method. In addition, any frequency can be used as a discharge frequency used in the plasma CVD method when the buffer layer is manufactured in the present invention, and even at a high frequency of 1 MHz or more and less than 50 MHz, which is industrially called an RF frequency band, the VHF band is used. 50MHz or more, called 450M
A high frequency of not more than Hz can be suitably used.

The temperature of the conductive substrate when depositing the buffer layer is 50 to 450 ° C., more preferably 100 to 3 ° C.
Preferably, the temperature is adjusted to 00 ° C.

(Other Layers) The photoreceptor of the present invention comprises:
In addition to the above surface layer, buffer layer, and photoconductive layer, a lower blocking layer may be provided between the photoconductive layer and the conductive substrate.

When the lower blocking layer 102 is provided, it is generally based on a-Si (H, X),
By including a dopant such as a group V element, the conductivity type can be controlled and the ability to inhibit the injection of carriers from the conductive substrate can be provided. In this case, if necessary,
Adjust the stress by containing at least one or more atoms selected from carbon atoms, nitrogen atoms and oxygen atoms,
It may have a function of improving the adhesion of the photosensitive layer.

Hereinafter, an example of a procedure for manufacturing a non-single-crystal silicon photoconductor using the apparatus shown in FIG. 5 will be described. FIG. 5 is a diagram schematically showing an example of an image carrier deposition apparatus by an RF plasma CVD method using a high frequency power supply.

This apparatus is roughly classified into a reaction vessel 2110
Device 2100 having source gas, source gas supply device 220
0, an exhaust device (not shown) for reducing the pressure inside the reaction vessel 2110. The conductive substrate 21 connected to the ground is provided in the reaction vessel 2110 in the deposition apparatus 2100.
12, a heater 2113 for heating the conductive substrate, a source gas introduction pipe 2114, and a high frequency power supply 2120 are connected via a high frequency matching box 2115.

The raw material gas supply device 2200 includes SiH ₄ ,
_{H 2, CH 4, NO,} B 2 H 6, such as raw material gas cylinder CF ₄ 2,221 to 2,226 and the valve 2231 to 2,236, the pressure regulator 2261-2266, inlet valve 2241-2
246, outflow valves 2251 to 2256, and mass flow controllers 2211 to 2216. A gas cylinder filled with each source gas is connected to a source gas introduction pipe 2114 in a reaction vessel 2110 via an auxiliary valve 2260. The conductive substrate 2112 is connected to ground by being placed on a conductive cradle.

Hereinafter, an example of a procedure for producing an image carrier using the apparatus shown in FIG. 5 will be described. The conductive base 2112 is placed in the reaction vessel 2110, and the inside of the reaction vessel 2110 is evacuated by an exhaust device (not shown) (for example, a vacuum pump). Subsequently, the temperature of the conductive substrate 2112 is controlled to a desired temperature of 20 ° C. to 500 ° C. by the heater 2113 for heating the conductive substrate. Next, a source gas for forming an image carrier is caused to flow into the reaction vessel 2110. For the introduction of the raw material gas, it is confirmed that the valves 2231 to 2236 of the gas cylinder and the leak valve 2117 of the reaction vessel are closed, and the inflow valves 2241 to 2246 and the outflow valves 2251 to 225
6. Confirm that the auxiliary valve 2260 is open, open the main valve 2118, and exhaust the reaction vessel 2110 and the gas supply pipe 2116.

Thereafter, the reading of the vacuum gauge 2119 becomes 0.67.
When the pressure reaches mPa, the auxiliary valve 2260 and the outflow valves 2251 to 2256 are closed. Then the raw material gas cylinder 2
From 221 to 2226, each gas is supplied to a valve 2231 to 223.
6 is opened and introduced, and each gas pressure is adjusted to 2 kg / cm ² (0.2 MPa) by the pressure adjusters 2261 to 2266. Next, the inflow valves 2241 to 2246 are gradually opened, and each gas is supplied to the mass flow controllers 2211 to 2216.
Introduce within.

After the preparation for film formation is completed by the above procedure, first, a photoconductive layer is formed on the conductive base 2112.

That is, when the conductive substrate 2112 reaches a desired temperature, the necessary one of the outflow valves 2251 to 2256 and the auxiliary valve 2260 are gradually opened,
A desired source gas is supplied from each source gas cylinder 2221 to 2226 through a source gas introduction pipe 2114 to a reaction vessel 2110.
Introduce within. Next, each mass flow controller 22
According to 11 to 2216, each source gas is adjusted so as to have a desired flow rate. At this time, the inside of the reaction vessel 2110 is 13
Vacuum gauge 211 so that a desired pressure of 3.3 Pa or less is obtained.
9 while adjusting the opening of the main valve 2118.

When the internal pressure is stabilized, the high-frequency power supply 21
20 is set to a desired power, for example, a frequency of 1 MHz to
A high frequency power of 450 MHz, for example, 13.56 MHz is supplied to the cathode electrode 2111 through the high frequency matching box 2115 to generate a high frequency glow discharge. Each source gas introduced into the reaction vessel 2110 is decomposed by the discharge energy, and a photoconductive layer composed of a desired non-single-crystal material containing silicon atoms as a main component is deposited on the conductive base 2112. After the desired layer thickness is formed, the supply of the high-frequency power is stopped, and each outflow valve 2251 to
By closing 2256, the flow of each source gas into the reaction vessel 2110 is stopped, and the formation of the photoconductive layer is completed. Known compositions and layer thicknesses of the photoconductive layer can be used.

When a surface layer is formed on the photoconductive layer,
Basically, the above operation may be repeated.

FIG. 4 is a diagram schematically showing an example of an apparatus for depositing a photosensitive member by a VHF plasma CVD method using a VHF power supply. This apparatus is a deposition apparatus 210 shown in FIG.
0 is replaced by the deposition apparatus 3100 of FIG.

The formation of a deposited film in this apparatus by the VHF plasma CVD method can be performed basically in the same manner as in the case of the RF plasma CVD method. However, the applied high frequency power is 50 MHz to 450 MHz, for example, a frequency of 105 M
Hz VHF power supply, pressure is 13.3 mP
a is kept lower than that of the RF plasma CVD method of about 13.3 Pa.

First, the conductive substrate 31 is placed in the reaction vessel 3110.
12 is installed. Then, the inside of the reaction vessel 3110 is exhausted through an exhaust pipe 3121 by an exhaust device (not shown) (for example, a diffusion pump). Subsequently, the conductive substrate 3112 is heated by the substrate heating heater 3113. Then, gas is introduced from a gas introduction pipe (not shown). In this apparatus, in the discharge space 3130 surrounded by the conductive base 3112, the introduced source gas is supplied to the matching box 31.
Glow discharge generated by introducing VHF power into the discharge space 3130 through 15 excites and dissociates, and a predetermined deposited film is formed on the conductive substrate 3112. At this time, the conductive support is rotated at a desired rotation speed by a rotation motor 3120 for rotating the conductive support in order to achieve uniform layer formation.

Next, the outline of the electrophotographic method and apparatus of the present invention will be described. According to the electrophotographic method of the present invention, as described above, a specific a-Si photosensitive member is charged by contact charging, an electrostatic latent image is formed by image exposure (IAE), and an electrostatic latent image is formed with a specific toner described later. Is developed. The electrophotographic method of the present invention only needs to include such steps, and may include other steps such as fixing and pre-exposure.

The electrophotographic apparatus of the present invention is not particularly limited as long as the apparatus can realize the above-described electrophotographic method. It can be manufactured by using a known technique, and various conventionally known means can be suitably used as long as it has a function to be realized.

FIG. 3 is a schematic diagram showing an example of the electrophotographic apparatus according to the present invention. The electrophotographic apparatus according to the present embodiment includes a rotating image carrier, a charging unit that charges a surface of the image carrier, a latent image forming unit that forms an electrostatic latent image on a charged surface of the image carrier, Developing means for developing the electrostatic latent image as a toner image by attaching toner to the surface of the image carrier, transfer means for transferring the toner image to a recording medium, and fixing an unfixed toner image to the recording medium And a fixing unit for causing the fixing device to perform the fixing.

[Image Carrier] In FIG. 3, reference numeral 201 denotes a rotating drum type electrophotographic image carrier (also simply referred to as "image carrier") as an image carrier. The copying machine of this embodiment uses reversal development, and the image carrier 201 has a diameter of, for example, 3 mm.
This is a 0 mm negative image carrier, on which the above-mentioned surface layer, photoconductive layer and the like are formed. The image carrier 201 is rotationally driven in the direction of the arrow at a surface speed of, for example, 200 mm / sec.

[Charging] 202 is a conductive elastic roller (hereinafter referred to as a “charging roller”) which is a charged particle carrier as a flexible contact charging member disposed in contact with the image carrier 201 with a predetermined pressing force. ”). The outer peripheral surface of the charging roller 202 is coated with and charged with charged particles in advance, and the charged particles are present in a charging nip portion with the image carrier 201.

In the present embodiment, the charging roller 202 is rotated at a peripheral speed of 100% in a direction (counter) opposite to the rotation direction of the image carrier 201 in the charging nip portion. Contact with a relative speed difference. Then, a predetermined charging bias is applied to the charging roller 202 from a charging bias power supply. As a result, the outer peripheral surface of the image carrier 201 is uniformly contact-charged to a predetermined polarity and potential by the injection charging method.

In this embodiment, the potential of the developing portion of the image carrier 201 is 150 V to 800 V, preferably 250 V to 6 V.
A charging bias is applied to the charging roller 202 from a charging bias power source so that the charging process is uniformly performed at 00V, more preferably 300V to 450V. If the voltage is lower than 150 V, the toner cannot be developed from the toner carrier to the a-Si photosensitive member, and the toner may accumulate to cause adverse effects such as low image density. On the other hand, when the voltage exceeds 800 V, the amount of current passing through the charging member is increased, so that the deterioration of the charging member is accelerated, and the applied voltage is increased, which may cause partial discharge. The charging roller, the charged particles M, the injection charging, and the like will be described in detail in another section.

[Exposure] 203 is intensity-modulated from a laser beam scanner (exposure device) or the like, which is a latent image forming means including a laser diode and a polygon mirror, in accordance with a time-series electric digital pixel signal of target image information. The latent image forming means outputs a laser beam 203, and scans the uniformly charged surface of the image carrier 201 with the laser beam. By this scanning exposure, an electrostatic latent image corresponding to the target image information is formed on the surface of the image carrier 201.

The light source used for the electrostatic latent image forming means is not limited to the laser beam scanner, but may be an LED array. In this case, the LED at the position corresponding to the target image information is turned on, and the image is turned on. An electrostatic latent image is formed on the surface of the carrier 201. More specifically, on the charged surface of the image carrier,
During development, light is irradiated to a portion to be an image portion to which toner is to be attached, thereby attenuating the potential of a predetermined portion of the charged surface of the image carrier to form an electrostatic latent image (image exposure: IAE).

[Development] 204 is a developing device as a developing means. The electrostatic latent image formed on the image carrier 201 is developed by the developing device 204 as a toner image. Here, a negatively charged toner is used as the toner 205. The developing unit is not particularly limited as long as it is a developing unit capable of performing both development and cleaning. For example, a developing container for storing toner and a conductive developing sleeve provided at an opening of the developing container for carrying and transporting the toner are provided. A magnetic field generating means such as a magnet fixed in the developing sleeve to form a plurality of magnetic fields; and a toner regulating member (for example, an elastic blade contacting the sleeve, A metal blade that regulates the layer thickness of the toner by concentrating a magnetic field at the tip, and a known developing unit that can apply a desired developing bias to the developing sleeve. I can do it.

[Transfer] Reference numeral 206 denotes a transfer roller of medium resistance, which is a transfer means serving as a contact transfer means.
The transfer nip portion is formed by pressing the transfer nip portion 01 at a predetermined pressure. A transfer material 207 as a recording medium (recording medium) is supplied to the transfer nip from a paper supply unit (not shown) at a predetermined timing, and a predetermined transfer bias voltage, here positive charge, is applied to the transfer roller 206. By being applied, the toner image on the image carrier 201 side, in this case, the negatively charged toner, is sequentially transferred to the surface of the transfer material 207 fed to the transfer nip portion by electrostatic force and pressing force. . In the present invention, the transfer unit is not particularly limited, and a known transfer unit can be used.

[Fixing] 209 is a fixing device such as a heat fixing system. The transfer material 207 having received the transfer of the toner image on the image carrier 201 is separated from the surface of the image carrier 201 and introduced into the fixing device 209, where the toner image is fixed and an image formed product (print, copy) is received. Is discharged out of the apparatus. In this embodiment, a heating and pressing fixing unit is illustrated as shown in the figure, but the present invention is not limited to the above fixing unit, and various known fixing units can be suitably used. .

[Charging Roller] The charging roller 202 as a contact charging member in this embodiment is manufactured by forming a medium-resistance layer of rubber or foam on a cored bar.

The medium resistance layer is formulated with a resin (for example, urethane), conductive particles (for example, carbon black), a sulfide agent, a foaming agent, and the like, and is formed in a roller shape on a cored bar.
Thereafter, the surface is polished if necessary.

When the roller resistance of the charging roller 202 of this embodiment was measured, the resistance was 100 kΩ · cm. The roller resistance is measured by applying a voltage of 100 V between the core metal and the aluminum substrate while the charging roller 202 is pressed against an aluminum substrate having a diameter of 30 mm so that a total pressure of 1 kg is applied to the core metal of the charging roller 202. did.

Here, it is important that the charging roller 202 as a contact charging member functions as an electrode. That is, it is necessary to obtain a sufficient contact state with the member to be charged by providing elasticity, and at the same time, it is necessary to have a resistance low enough to charge the moving member to be charged. On the other hand, it is necessary to prevent voltage leakage when a low withstand voltage defect site such as a pinhole is present in the member to be charged. When an electrophotographic image carrier is used as a member to be charged, the volume resistivity is 1 × 10 ³ to 1 × 10 ⁸ Ω.
Cm, and a resistance of 10 ⁴ to 10 ⁷ Ω · cm is more desirable to obtain sufficient chargeability and leakage resistance. If the resistance of the charging roller is out of the above range, the above-described charging and leakage resistance may not be achieved.

The surface of the charging roller 202 desirably has a porous body surface represented by micro unevenness capable of holding charged particles.

The hardness of the charging roller 202 is asker C
The hardness is preferably 50 degrees or less, but if the hardness is too low, the shape becomes unstable, so that the contact property with the member to be charged is deteriorated. If the hardness is too high, not only the charging nip portion cannot be secured with the member to be charged, but also Since the microscopic contact with the surface of the member to be charged deteriorates, the Asker C hardness is more preferably 25 to 50 degrees. The hardness of the charging roller 202 is
It can be measured using an Asker-C micro rubber hardness meter manufactured by Kobunshi Keiki Co., Ltd. More specifically, the hardness of the charging roller is measured at any five points of the charging roller using the present hardness meter, and the average value of the five points is defined as the hardness of the charging roller.

The material of the charging roller 202 is not limited to an elastic foam.
EPDM, urethane, NBR, silicone rubber, IR
For example, a rubber material in which a conductive substance such as carbon black or a metal oxide is dispersed for the purpose of resistance adjustment, or a foamed material thereof may be used. Further, it is also possible to adjust the resistance by using an ionic conductive material without dispersing the conductive substance.

The charging roller 202 is disposed by being pressed against the image carrier 201 as a member to be charged with a predetermined pressing force against elasticity. In this embodiment, a charging nip portion having a width of several mm is formed. It is.

[Charged Particles] The charged particles used in the present invention are mainly composed of conductive fine powder, and the average particle diameter of the conductive fine powder is 0.1 to 10 μm. If the average particle diameter of the charged particles is small, the content of the charged particles with respect to the entire toner must be set small in order to prevent a decrease in the developing property. If the average particle size of the charged particles is less than 0.1 μm, an effective amount of the charged particles cannot be secured, and in the charging step, adhesion to the insulative transfer residual toner on the contact charging member and
A sufficient amount of charged particles to overcome the charging inhibition due to the contamination and make the charging of the image carrier good can not be interposed in the nip portion between the charging member and the image carrier or the charging area in the vicinity thereof, Poor charging easily occurs. In this respect, the average particle size of the conductive fine powder is preferably 0.15 μm.
m or more, more preferably 0.2 μm or more and 5 μm or less.

The conductive fine powder has an average particle diameter of 10 μm.
If it is larger than m, the charged particles dropped from the charging member may shield or diffuse the exposure light for writing the electrostatic latent image, causing a defect in the electrostatic latent image and deteriorating the image quality. Furthermore,
When the average particle size of the conductive fine powder that is a charged particle is large,
Since the number of particles per unit weight is reduced, the charged particles are sequentially transferred to the nip portion between the charging member and the image carrier or a charged area in the vicinity thereof in consideration of the reduction and deterioration due to the dropping of the charged particles from the charging member. In order for the charged particles to be continuously supplied and interposed, and in order for the contact charging member to maintain dense contact with the image carrier via the charged particles and stably obtain good chargeability, the charged particles are The content in the whole toner must be increased. However, if the content of the charged particles is too large, particularly under a high humidity environment, the developing property is reduced,
This causes a reduction in image density and toner scattering.

In the present embodiment, conductive zinc oxide particles having a specific resistance of 10 ⁷ Ω · cm and an average particle diameter of 1.5 μm are used as the charged particles.

In the measurement of the average particle size and the particle size distribution of the charged particles in the present invention, LS-L manufactured by Beckman Coulter, Inc. was used.
The measurement was performed in a measurement range of 0.04 to 2000 μm using a liquid module attached to a 230-type laser diffraction particle size distribution analyzer. As a measurement method, a trace amount of a surfactant was added to 10 ml of pure water, and a conductive fine powder sample 1 was added thereto.
After adding 0 mg and dispersing for 10 minutes with an ultrasonic dispersing machine (ultrasonic homogenizer), measurement was performed with a measuring time of 90 seconds and one measurement.

In the present invention, the method of adjusting the particle size and the particle size distribution of the charged particles is not limited to the method of setting the manufacturing method and the manufacturing conditions so that the desired particle size and the particle size distribution of the primary particles of the charged particles can be obtained at the time of manufacturing. In addition, a method of agglomerating small particles of primary particles, a method of pulverizing large particles of primary particles, a method of classification, and the like are further possible, and further, a part of the surface of base particles having a desired particle size and particle size distribution. Or a method of attaching or fixing conductive particles to all,
A method using conductive fine particles having a form in which a conductive component is dispersed in particles having a desired particle size and particle size distribution is also possible, and it is also possible to adjust the particle size and particle size distribution of the charged particles by combining these methods. It is.

When the charged particles are constituted as an aggregate, the particle size is defined as the average particle size of the aggregate. There is no problem that the charged particles exist not only in the state of primary particles but also in the state of aggregation of secondary particles. Regardless of the state of aggregation, the form is not particularly limited as long as it can be provided as an aggregate in the nip portion between the charging member and the image bearing member or in a charging region in the vicinity thereof and realize the function of assisting or promoting charging.

The resistance of the charged particles is preferably 10 ⁹ Ω · cm or less. If the resistance of the charged particles is greater than 10 ⁹ Ω · cm, the charged particles are interposed in the nip portion between the charging member and the image bearing member or in the charged area in the vicinity of the nip portion, and the image is carried through the charged particles of the contact charging member. Even if the close contact with the body is maintained, the charge promotion effect for obtaining good chargeability may not be obtained. In order to sufficiently extract the effect of accelerating the charging of the charged particles and stably obtain good charging properties, the resistance of the charged particles must be smaller than the resistance of the surface portion of the contact charging member or the contact portion with the image carrier. Is preferred.

Further, the resistance of the charged particles is 10 ⁶ Ω · cm
It is preferable that the following conditions are satisfied in order to overcome the charging inhibition due to the adhesion and mixing of the insulating transfer residual toner to the contact charging member and to perform better charging of the image carrier. On the other hand, the resistance value is not good or too low, 1 × 10 to the charging particles promotes the development charged charged non-image portion ^-1 Omega
・ It is preferably at least cm. In this embodiment, 1 ×
Use a thing of 10 ⁷ Ω · cm.

The resistance was measured by the tablet method and normalized. That is, a powder sample of about 0.5 g is placed in a cylinder having a bottom area of 2.26 cm ² , 15 kg of pressure is applied to the upper and lower electrodes, and at the same time, a voltage of 100 V is applied to measure the resistance value. To calculate the specific resistance.

The charged particles are desirably white or nearly transparent so as not to hinder the exposure of the latent image. Further, it is preferably non-magnetic. Further, in consideration of the fact that the charged particles are partially transferred from the image carrier to the recording material P, in color recording, transparent, white or light-colored charged particles are preferable, and more preferably, the charged particles are exposed to light. The light transmittance is preferably 30% or more.

In the present invention, the light transmittance of the particles was measured according to the following procedure. The transmittance is measured with one layer of the conductive fine powder of a transparent film having an adhesive layer on one side fixed. The light was irradiated from the vertical direction of the sheet, and the light transmitted through the back of the film was collected and the amount of light was measured. The transmittance of the particles was calculated as a net light amount from the light amount when the particles were attached only to the film. Actually, it was measured using a 310T transmission densitometer manufactured by X-Rite.

As the material of the charged particles, zinc oxide is used in the present embodiment, but the material is not limited to zinc oxide. Fine carbon powder such as carbon black, graphite;
Fine metal powders such as copper, gold, silver, aluminum and nickel; metals such as zinc oxide, titanium oxide, tin oxide, aluminum oxide, indium oxide, silicon oxide, magnesium oxide, barium oxide, molybdenum oxide, iron oxide, and tungsten oxide Oxides; metal compounds such as molybdenum sulfide, cadmium sulfide, potassium titanate, or composite oxides thereof can be used by adjusting the particle size and particle size distribution as needed. Among them, zinc oxide, tin oxide,
Metal oxide fine particles of titanium oxide are particularly preferred.

For the purpose of controlling the resistance of the conductive metal oxide, a metal oxide doped with an element such as antimony and aluminum, and fine particles having a conductive material on the surface can also be used. For example, titanium oxide fine particles surface-treated with tin oxide / antimony, stannic oxide fine particles doped with antimony, or stannic oxide fine particles. In addition, various conductive particles such as a mixture of conductive inorganic particles of other metal oxides such as titanium oxide and alumina with an organic substance, or a surface-treated mixture thereof can be used. You may mix and use two or more. Examples of commercially available conductive titanium oxide fine particles treated with tin oxide and antimony include EC-300 (Titanium Industry Co., Ltd.) and E
T-300, HJ-1, HI-2 (the above, Ishihara Sangyo Co., Ltd.), WP (Mitsubishi Materials Corporation) and the like. Examples of commercially available antimony-doped conductive tin oxide include T-1 (Mitsubishi Materials Corporation) and SN
-100P (Ishihara Sangyo Co., Ltd.) and commercially available stannic oxide include SH-S (Nippon Chemical Industry Co., Ltd.).

In addition to the above-mentioned conductive fine powder, the charged particles may have other properties such as conductivity, light transmittance, color tone, specific gravity, and fluidity. Fine powder may be added. The fine powder only needs to adjust the desired physical properties of the charged particles, and those having no conductivity can be used.

The method of interposing charged particles in the contact portion is not particularly limited, but includes a method in which the charging means includes a charged particle replenishing means for supplying the charged particles to the surface of the charging roller, or a method in which the charged particles are externally added to the toner. And indirectly intervening.

[Injection Charging] By interposing charged particles in the charging nip portion A between the image bearing member 201 and the charging roller 202 serving as a contact charging member, frictional resistance is large due to the lubricant effect of the particles. Even if it is difficult for the charging roller to contact the carrier 201 with a speed difference, the charging roller is easily and effectively provided with a speed difference with respect to the image carrier 201 surface. The charging roller 202 can be brought into contact with the charging roller 202.
Are in intimate contact with the surface of the image carrier 201 via the charged particles and come into contact with the surface of the image carrier 201 more frequently.

By providing a sufficient speed difference between the charging roller 202 and the image carrier 201, the charging roller 2
02 and the charging nip portion of the image carrier 201, the chance of contact of the charged particles with the image carrier 201 is remarkably increased, and a high contact property can be obtained. The charged particles existing on the surface of the image carrier 201
1 can be directly injected into the charging roller 2.
In the contact charging of the image carrier 201 by 02, the injection charging mechanism becomes dominant due to the presence of charged particles.

As a configuration for providing a speed difference, the charging roller 202 is rotationally driven or fixed to provide a speed difference from the image carrier 201. Preferably, the charging roller 2
02 is rotated, and the rotation direction is
Desirably, the rotation direction is opposite to the direction of movement of the 01 surface.

[Toner] The toner used in the present invention is as follows.
A magnetic toner, comprising toner particles containing at least a binder resin and a magnetic substance, and inorganic fine powder, and having an average circularity of 0.950 or more, wherein 79.6 k of the magnetic toner is used.
Saturation magnetization in A / m (1000 Oe) below is characterized in that at ^{10Am 2 / kg (emu / g} ) or more 50 Am ² / kg or less. The toner used in the present invention is not particularly limited as long as it has the above physical properties,
Various techniques known in the art can be used for the manufacturing method and the constituent materials.

The toner used in the present invention can be produced by a pulverizing method. However, the toner particles obtained by the pulverizing method are generally irregular in shape and are indispensable for the toner used in the present invention. Some average circularity is 0.95
In order to obtain a desirable physical property of 0 or more, it is necessary to perform a mechanical / thermal or some special treatment. Therefore, in the present invention, it is preferable to produce the toner particles by a suspension polymerization method (hereinafter, the toner produced by the polymerization method is also referred to as “polymerized toner”). However,
Similar effects can be obtained with pulverized toners other than the polymerized toners described below, provided that the sphericity is within the conditions.

The polymerized toner has a substantially uniform spherical shape and a small variation in the particle size, so that the polymerized toner has excellent fluidity. In addition, a colorant is not exposed on the surface of the particle, and uniform triboelectrification is obtained. This is advantageous for high image quality. In addition, wax can be included, and good fixing properties and offset resistance can be obtained. For this reason, the adoption is gradually spreading in high image quality machines.

In the method for producing a polymerized toner relating to the electrophotographic method of the present invention, generally, a magnetic material, a release agent, a charge control agent, and, if necessary, a colorant, a crosslinking agent,
Other additives such as a plasticizer and, for example, an organic solvent to be added to reduce the viscosity of the polymer formed in the polymerization reaction, a polymer, a dispersant, and the like are added as appropriate, and a homogenizer, a ball mill, a colloid mill, an ultra It is uniformly dissolved or dispersed by a disperser such as a sonic disperser, and the obtained monomer system is suspended in an aqueous medium containing a dispersion stabilizer. At this time, it is preferable to use a high-speed disperser, such as a high-speed stirrer or an ultrasonic disperser, to make the desired toner particle size at a stretch in order to adjust the particle size of the obtained toner particles. As the timing of the addition of the polymerization initiator, it may be added simultaneously with the addition of other additives in the polymerizable monomer,
You may mix immediately before suspending in an aqueous medium. Immediately after granulation and before the initiation of the polymerization reaction, a polymerization initiator dissolved in a polymerizable monomer or a solvent can be added. As these raw materials, those usually used in the production of toner can be used.

As for the production conditions of the polymerized toner, the polymerization is carried out at a polymerization temperature of 40 ° C. or higher, generally 50 to 90 ° C. When the polymerization is carried out in this temperature range, the release agent and waxes to be sealed inside are precipitated by phase separation, and the encapsulation becomes more complete. In order to consume the remaining polymerizable monomer, the reaction temperature is set to 90 at the end of the polymerization reaction.
It is possible to increase to ~ 150 ° C.

Further, the toner used in the present invention may be prepared by a dispersion polymerization method in which an aqueous organic solvent which is soluble in a monomer and in which a polymer obtained is insoluble is used to directly form a toner, or a toner having a water-soluble polar polymerization initiator. Production is also possible by a method of producing a toner using an emulsion polymerization method typified by a soap-free polymerization method in which a polymer is directly polymerized below to form a toner, and a method of associating and aggregating polymer particles and the like obtained by emulsion polymerization.

After polymerization is completed, the polymerized toner particles are filtered, washed and dried by a known method, mixed with an inorganic fine powder and adhered to the surface to obtain a toner.
In addition, it is also a desirable embodiment of the present invention to insert a classifying step into the manufacturing process and cut coarse or fine powder.

Since the toner obtained by this suspension polymerization method has a substantially spherical shape of individual toner particles, a toner having an average circularity of 0.950 or more and satisfying the physical properties essential for the present invention can be obtained. Such toners have high transferability because the charge amount distribution is relatively uniform.

The toner used in the present invention has toner particles containing at least a binder resin and a magnetic substance, and inorganic fine powder. As the binder resin, various types of binder resins conventionally known can be used. As such a binder resin, for example, a homopolymer of styrene such as polystyrene and polyvinyltoluene and a substituted product thereof;
Styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer,
Styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-dimethylaminoethyl acrylate copolymer, styrene-meta Methyl acrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-dimethylaminoethyl methacrylate copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl Styrene copolymers such as ethyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-maleic acid copolymer, and styrene-maleic acid ester copolymer Polymer; polymethyl methacrylate, polymethyl methacrylate Butyl methacrylate, polyvinyl acetate, polyethylene, polypropylene, polyvinyl butyral, silicone resin, polyester resin, polyamide resin, epoxy resin, polyacrylic resin, rosin, modified rosin, terpene resin, phenol resin, aliphatic or alicyclic hydrocarbon Resins and aromatic petroleum resins can be exemplified. These can be used alone or in combination of two or more.

The polymerizable monomers suitably used in the suspension polymerization method include, for example, styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene,
p-methoxystyrene, styrene monomers such as p-ethylstyrene, methyl acrylate, ethyl acrylate,
Acrylic esters such as n-butyl acrylate, isobutyl acrylate, n-propyl acrylate, n-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, 2-chloroethyl acrylate, phenyl acrylate , Methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, Examples thereof include methacrylates such as dimethylaminoethyl methacrylate and diethylaminoethyl methacrylate, and other acrylonitrile, methacrylonitrile, and acrylamide. Or it may be used two or more. Among the above-mentioned monomers, it is preferable to use the above-mentioned monomer so as to include at least styrene or a styrene derivative from the viewpoint of the developing characteristics and durability of the obtained magnetic toner.

Examples of the polymerization initiator that can be used in polymerizing the polymerizable monomer include, for example,
2,2′-azobis- (2,4-dimethylvaleronitrile), 2,2′-azobisisobutyronitrile, 1,1 ′
-Azobis (cyclohexane-1-carbonitrile),
Azo or diazo polymerization initiators such as 2,2'-azobis-4-methoxy-2,4-dimethylvaleronitrile and azobisisobutyronitrile, benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, cumene Hydroperoxide, 2,4-dichlorobenzoyl peroxide, lauroyl peroxide, t-butylperoxy-2-
A peroxide-based polymerization initiator such as ethylhexanoate can be exemplified, and one or more of these can be used.

Examples of the cross-linking agent that can be used in polymerizing the polymerizable monomer include, for example, various cross-linking agents that are conventionally known as compounds having two or more polymerizable double bonds. For example, aromatic divinyl compounds such as divinylbenzene and divinylnaphthalene; having two double bonds such as ethylene glycol diacrylate, ethylene glycol dimethacrylate and 1,3-butanediol dimethacrylate can be used. Examples thereof include carboxylic acid esters; divinyl compounds such as divinylaniline, divinyl ether, divinyl sulfide, and divinyl sulfone; and compounds having three or more vinyl groups, and one or more of these can be used.

As the dispersion stabilizer suitably used in the suspension polymerization method, known surfactants and organic / inorganic dispersants can be used. Above all, inorganic dispersants are unlikely to produce harmful ultrafine powders, and because of their steric hindrance, they have dispersion stability, so even if the reaction temperature is changed, their stability is not easily lost, and they are easy to wash and do not adversely affect the toner. Can be preferably used.

Examples of the surfactant include sodium dodecylbenzene sulfate, sodium tetradecyl sulfate,
Examples thereof include sodium pentadecyl sulfate, sodium octyl sulfate, sodium oleate, sodium laurate, sodium stearate, and potassium stearate, and one or more of these can be used.

Examples of the organic dispersant include polyvinyl alcohol, gelatin, methyl cellulose, methyl hydroxypropyl cellulose, ethyl cellulose, sodium salts of carboxymethyl cellulose, polyacrylic acid and salts thereof, and starch. Alternatively, two or more kinds can be used.

Examples of the inorganic dispersant include polyvalent metal phosphates such as calcium phosphate, magnesium phosphate, aluminum phosphate and zinc phosphate, carbonates such as calcium carbonate and magnesium carbonate, calcium metasilicate, calcium sulfate and barium sulfate. And inorganic oxides such as calcium hydroxide, magnesium hydroxide, aluminum hydroxide, silica, bentonite, and alumina, and one or more of these can be used.

The toner used in the present invention may include waxes for adjusting the releasability and plasticity. Examples of such waxes include paraffin wax, microcrystalline wax, petroleum wax such as petrolactam and its derivatives, montan wax and its derivatives, hydrocarbon wax and its derivatives by Fischer-Tropsch method, and polyethylene. Natural waxes and derivatives thereof such as polyolefin waxes and derivatives thereof, carnauba wax and candelilla wax, and derivatives include oxides, block copolymers with vinyl monomers, and graft modified products. Furthermore, fatty acids such as higher aliphatic alcohols, stearic acid and palmitic acid, or compounds thereof, acid amide waxes, ester waxes, ketones, hydrogenated castor oil and derivatives thereof, vegetable waxes, and animal waxes can be exemplified. These may be used alone or in combination of two or more.

Further, as the toner used in the present invention, a charge control agent for controlling the chargeability of the toner can be used. Examples of such charge control agents include, as negative charge control agents, salicylic acid, alkyl salicylic acid, dialkyl salicylic acid, naphthoic acid, metal compounds of aromatic carboxylic acids such as dicarboxylic acids, metal salts of azo dyes or azo pigments, or Metal complexes, high molecular compounds having a sulfonic acid or carboxylic acid group in the side chain, boron compounds, urea compounds, silicon compounds, calixarenes can be exemplified as negative charge control agents, and these may be used alone or in combination of two or more. Can be used. Examples of the positive charge control agent include a quaternary ammonium salt, a polymer compound having the quaternary ammonium salt in a side chain, a guanidine compound, a nigrosine compound, and an imidazole compound. One or two or more can be used.

In the toner used in the present invention, a coloring agent can be used if necessary. Such colorants include, for example, magnetic or non-magnetic inorganic compounds,
Known dyes and pigments, more specifically, for example, cobalt, ferromagnetic metal particles such as nickel, or chromium, manganese, copper, zinc, aluminum, alloys such as rare earth elements, particles such as hematite, Examples include titanium black, nigrosine dye / pigment, carbon black, and phthalocyanine, and one or more of these can be used. As the coloring agent, a colorant that has been subjected to a hydrophobic treatment in the same manner as a magnetic substance or an inorganic fine powder described later may be used.

As the magnetic substance contained in the toner used in the present invention, a known magnetic substance can be used. Examples of such a magnetic material include those mainly containing iron oxide such as triiron tetroxide and γ-iron oxide,
One or two or more of these can be used. The magnetic material may further contain other elements such as phosphorus, cobalt, nickel, copper, magnesium, manganese, aluminum, and silicon. The saturation magnetization of the toner can be adjusted by the type of the magnetic material used, the amount of the magnetic material, and the like.

The surface of the magnetic material is preferably subjected to a hydrophobic treatment, and the hydrophobic treatment can be performed by a known method using a known treating agent. Examples of the treating agent used in such a hydrophobizing treatment include coupling agents such as a silane coupling agent and a titanium coupling agent that are bonded to the surface of the magnetic body while being hydrolyzed in an aqueous medium, in particular, a silane coupling agent. Preferably, as such a silane coupling agent, for example, vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, methyltrimethoxysilane, methyltriethoxysilane, isobutyltriethoxysilane Methoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, trimethylmethoxysilane, hydroxypropyltrimethoxysilane, phenyltrimethoxysilane, n-hexadecyltrimethoxysilane, n-octadecyltrimethoxysilane Can be exemplified down, it is possible to use more of these one or two or.

The toner used in the present invention contains an inorganic fine powder for the purpose of adjusting the fluidity and the like of the toner. Examples of such an inorganic fine powder include silica, alumina and titania, and one or more of these can be used. More specifically, for example, both the so-called dry method produced by the vapor phase oxidation of silicon halide or fumed silica as the silicic acid fine powder, and the so-called wet silica produced from water glass and the like are both used. there is a usable, less silanol groups on the inner surface and the silica fine powder, also Na ₂ O, towards less dry silica of manufacture residues of SO ₃ ^2-like. In the case of fumed silica, for example, a composite fine powder (complex oxide) of silica and another metal oxide is obtained by using another metal halide compound such as aluminum chloride, titanium chloride or the like together with a silicon halide compound in the production process. It is also possible, and the inorganic fine powder also includes them.

It is preferable that the inorganic fine powder is blended in a total amount of 0.1 to 3.0% by mass based on the total amount of the toner. If the amount of the inorganic fine powder is less than 0.1% by mass, the effects of external addition of the inorganic fine powder (such as improvement in the fluidity and chargeability of the toner) may not be sufficiently exhibited. If the amount of the inorganic fine powder is more than 3.0% by mass, the fixability may be deteriorated.

Further, the inorganic fine powder has a primary particle size of 4 to
Preferably it is 100 nm. When the average particle size of the inorganic fine powder is smaller than the above range, the cohesiveness of the inorganic fine powder is increased, and the image carrier and the like are damaged by the aggregates, so that image defects are likely to occur. If the average particle size of the inorganic fine powder is larger than the above range, the effect of improving the fluidity of the toner cannot be sufficiently obtained, and image defects due to insufficient charging of the toner are likely to occur.

The average particle size of the inorganic fine powder can be measured by various conventionally known measuring methods.
More specifically, the average particle size of the inorganic fine powder used in the present invention, magnified and photographed the toner with a scanning electron microscope,
While comparing the photograph of the toner mapped with the elements contained in the inorganic fine powder by the elemental analysis means such as XMA attached to the scanning electron microscope, the inorganic fine powder adhered or separated on the toner surface is removed. It can be measured by measuring 100 or more primary particles.

The inorganic fine powder has a specific surface area (BE)
(T value) is preferably from ²⁰ to 400 m ² / g.
The BET value may be measured before or after the hydrophobizing treatment since it is not so affected by the hydrophobizing treatment described later, but it is more practical to measure the BET value after the hydrophobizing treatment. It is preferable in grasping. The BET value of the inorganic fine powder can be calculated according to the BET method by using a specific surface area measuring apparatus Autosorb 1 (manufactured by Yuasa Ionics), adsorbing nitrogen gas on the sample surface, and using the BET multipoint method.

The surface of the inorganic fine powder is preferably subjected to a hydrophobic treatment. In the hydrophobizing treatment of the inorganic fine powder, a treating agent used according to the type of the inorganic fine powder may be appropriately selected. Examples of the treating agent used in such a hydrophobizing treatment include a silane coupling agent and a titanium cup. Coupling agents such as ring agents and known treatment agents such as silicone oil can be exemplified. The hydrophobic treatment of the inorganic fine powder can be performed in the same manner as or similar to the hydrophobic treatment of the magnetic substance.

It is more preferable that the inorganic fine powder has been subjected to hydrophobic treatment with silicone oil. Examples of the silicone oil used in such a hydrophobizing treatment include, for example, dimethyl silicone oil, methylphenyl silicone oil, α-methylstyrene-modified silicone oil, chlorophenyl silicone oil, and fluorine-modified silicone oil. One or more of these can be used.

The toner used in the present invention has an average circularity of 0.950 or more, preferably 0.970 or more. When the average circularity of the toner is larger than 0.950, the shape of the toner becomes closer to a sphere, the contact area between the toner particles and the image carrier becomes smaller, and the toner caused by the mirror image force, van der Waals force, etc. Adhesion of the particles to the image carrier is reduced, and transferability is improved. Further, when the average circularity is high, the magnetic toner forms uniform and thin spikes in the developing section, and it is possible to perform development faithful to the latent image, and an improvement in image quality can be expected. On the other hand, when the average circularity is smaller than 0.950, the above-described effects may not be obtained, which is not preferable.

The average circularity of the toner used in the present invention is used as a simple method for quantitatively expressing the shape of the particles. In the present invention, the flow particle image analyzer “FPIA-” manufactured by Toa Medical Electronics Co., Ltd. 1000 ", and the circularity (Ci) of each particle measured for a group of particles having a circle equivalent diameter of 3 μm or more is obtained by the following equation (1), and further as shown by the following equation (2). The value obtained by dividing the sum of the measured circularities of all the particles by the total number of particles (m) is defined as the average circularity (C).

[0154]

[Formula 1] Equation (1)

[0155] The measuring device "FPIA-1000" used in the present invention calculates the circularity of each particle, and then calculates the circularity.
In calculating the average circularity, the particles are classified into classes obtained by dividing the circularity from 0.40 to 1.00 into 61 according to the obtained circularity, and the average circularity is calculated using the center value and frequency of the division points. The calculation method is used. However, the error between the value of the average circularity calculated by this calculation method and the value of the average circularity calculated by the above-described calculation formula that directly uses the circularity of each particle is very small, and is substantially ignored. In the present invention, the concept of the above-described calculation formula that directly uses the circularity of each particle is used for the reason of handling data such as shortening of calculation time and simplification of calculation formula. However, such a calculation method partially modified may be used.

As a specific measuring method, about 5 mg of a developer is added to 10 ml of water in which about 0.1 mg of a surfactant is dissolved.
Is dispersed to prepare a dispersion, and ultrasonic waves (20 kHz, 5 kHz,
0W) to the dispersion for 5 minutes to bring the dispersion concentration to 5000
２20,000 / μl, and the measurement was performed using the above apparatus.
The average circularity of a particle group having a circle equivalent diameter of not less than μm is determined.

The average circularity in the present invention is an index of the degree of unevenness of the developer. The average circularity is 1.000 when the developer has a perfect spherical shape. It will be a small value.

The reason why the circularity is measured only for particles having a circle equivalent diameter of 3 μm or more in this measurement is as follows.
This is because the particle group having a circle-equivalent diameter of less than m includes a large number of particles of the external additive that are present independently of the toner particles, and the circularity of the toner particle group cannot be accurately estimated due to the influence. .

The toner used in the present invention has a weight average particle diameter of 3 to 3 from the viewpoints of development characteristics, transferability, chargeability and the like.
It is preferably 10 μm. If it is smaller than this range, the transfer efficiency is lowered and it becomes difficult to maintain the uniformity of charging. On the other hand, if the weight average particle size is too large, the developability is reduced and a high quality image cannot be formed.

The weight average particle size of the toner used in the present invention can be measured by various methods for measuring the weight average particle size of the powder. In the present invention, Coulter Multisizer (manufactured by Coulter Co., Ltd.) is preferred. And a measuring device to which an interface (manufactured by Nikkaki Co., Ltd.) for outputting a number distribution and a volume distribution and a PC9801 personal computer (manufactured by NEC) are connected.

The method of measuring the weight average particle size varies depending on the measuring device used. In the measuring device described above, a dispersant (for example, alkylbenzenesulfonic acid or the like) is added to an electrolytic aqueous solution (for example, ISOTON-II manufactured by Coulter Scientific Japan). Surfactant) as needed, a sample to be measured (toner) is added, dispersion treatment is performed using an ultrasonic disperser or the like, and the volume and number of toner particles of 2 μm or more are measured using the Coulter Multisizer using a 100 μm aperture. For example, a method of calculating the volume distribution and the number distribution of the toner particles from the measurement results and calculating the volume-based weight average particle diameter from the volume distribution can be exemplified.

79.6 of Magnetic Toner Used in the Present Invention
kA / m (1000 Oe) saturation magnetization under is ^{10~50Am 2 / kg (emu / g} ).

However, if the saturation magnetization of the toner in the magnetic field of 79.6 kA / m is less than 10 Am ² / kg, the magnetic force acts on the toner carrier, so that the toner spikes become unstable and the toner is charged. Image defects, such as fogging, uneven image density, and poor recovery of untransferred toner, are likely to occur. Magnetic field of magnetic toner 79.
If the saturation magnetization at 6 kA / m is larger than 50 Am ² / kg, when a magnetic force is applied to the toner, the fluidity of the toner is remarkably reduced due to magnetic aggregation, and the transferability is reduced, so that the transfer residual toner is increased. As the tendency of the toner particles and the conductive fine powder to behave together increases, the conductive fine powder adhering to and mixed with the charged particle carrier is reduced, and the contact portion between the charged particle carrier and the image carrier is reduced. In this case, the amount of the conductive fine powder interposed in the toner particles is relatively reduced with respect to the amount of the transfer residual toner.

In the present invention, the saturation magnetization of the magnetic toner is
It can be measured at room temperature of 25 ° C. with an external magnetic field of 79.6 kA / m using a vibrating magnetometer VSMP-1-10 (manufactured by Toei Industry Co., Ltd.).

The magnetic toner used in the present invention is:
It is also preferable to externally add a conductive fine powder. In the present invention, the content of the conductive fine powder with respect to the whole toner is,
The content is preferably 0.1 to 10% by mass. If the content of the conductive fine powder with respect to the entire toner is less than 0.1% by mass, the charging of the image carrier is improved by overcoming the charging inhibition due to the adhesion and mixing of the insulating transfer residual toner to the contact charging member. A sufficient amount of conductive fine powder to make
It cannot be interposed in the nip portion between the charging member and the image bearing member or in a charging region in the vicinity thereof, so that the charging property is reduced and charging failure may occur. On the other hand, if the content is more than 10% by mass, the amount of the conductive fine powder recovered by the developing and cleaning becomes too large, so that the chargeability and developability of the toner in the developing section are reduced, and the image density is reduced. The toner may be scattered. The content of the conductive fine powder with respect to the entire toner is more preferably 0.2 to 5% by mass.

[0166]

EXAMPLES The effects of the present invention will be specifically described below with reference to examples. Note that the present invention is not limited to these examples. Note that the physical properties measured in the examples were measured by the same methods as those described in the embodiments. In this example, "parts" refers to parts by mass.

Example 1 First, a mirror-finished aluminum conductive substrate having a diameter of 30 mm and a thickness of 2.5 mm was subjected to the following conditions under the conditions shown below using an RF plasma CVD apparatus shown in FIG. A lower blocking layer, a photoconductive layer, and a buffer layer were stacked on the cylinder. Furthermore, a surface layer made of aC: H containing a small amount of Si is laminated thereon, so that the silicon atom content (ratio of silicon atoms to the total amount of silicon atoms and carbon atoms) of the surface layer is different for negative charging. -Si photoreceptors (A1) to (A4) and (A) to (E) were produced. The RF frequency is 1
3.56 MHz was used.

[0168] <production conditions of the photoconductive> lower blocking layer _{SiH 4: 150ml / min (normal} : 25 ℃, 10 5 Pa) PH 3: 500ppm (SiH 4 criteria) NO: 10ml / min (normal ) Power: 200 W internal pressure : 67 Pa Base temperature: 240 ° C. Film thickness: 1 μm Photoconductive layer SiH ₄ : 200 ml / min (normal) Power: 500 W Internal pressure: 67 Pa Base temperature: 240 ° C. Film thickness: 25 μm Buffer layer SiH ₄ : 50 ml / min (normal) CH ₄ : 500 ml / min (normal) Power: 1500 W Internal pressure: 67 Pa Base temperature: 240 ° C. Film thickness: 0.5 μm Surface layer SiH ₄ : (A1) 0.15 ml / min (normal) (A2) 0.2 ml / min ( normal) (A3) 0.5m / Min (normal) (A4) 0.7 ml / min (normal) (A) 1.0 ml / min (normal) (B) 1.5 ml / min (normal) (C) 4.0 ml / min (normal) ( D) 6.0 ml / min (normal) (E) 8.0 ml / min (normal) CH ₄ : 100 ml / min (normal) Power: 1500 W Internal pressure: 67 Pa Base temperature: 50 ° C. Film thickness: 0.3 μm Thus, a polymerization toner (1) was prepared. 451 g of a 0.1 M Na ₃ PO ₄ aqueous solution was added to 709 g of ion-exchanged water and heated to 60 ° C., and then a 1.0 M CaCl ₂ aqueous solution 6 was added.
7.7 g was gradually added to obtain an aqueous medium containing Ca ₃ (PO ₄ ) ₂ .

Styrene 80 parts n-butyl acrylate 20 parts Unsaturated polyester resin 2 parts Saturated polyester resin 3 parts Negative charge control agent (monoazo dye-based Fe compound) 1 part Surface-treated hydrophobized magnetic material 90 parts The mixture was uniformly dispersed and mixed using a lighter (Mitsui Miike Kakoki Co., Ltd.). This monomer composition was heated to 60 ° C., and an ester wax mainly containing behenyl behenate (maximum endothermic peak in DSC of 72) was added thereto.
° C) 6 parts were added, mixed and dissolved, and the polymerization initiator 2, 2 'was added thereto.
-Azobis (2,4-dimethylvaleronitrile) [t1 /
2 = 140 minutes, at 60 ° C.].

The above polymerizable monomer system was charged into the above aqueous medium, and the mixture was heated at 10,000 rpm at 60 ° C. under a N ₂ atmosphere at 10,000 rpm using a TK homomixer.
The mixture was stirred for 5 minutes and granulated. Thereafter, the mixture was reacted at 60 ° C. for 6 hours while stirring with a paddle stirring blade. After that, the liquid temperature was 80 ° C.
The stirring was further continued for 4 hours. After the completion of the reaction, distillation was further performed at 80 ° C. for 2 hours. Thereafter, the suspension was cooled, hydrochloric acid was added to dissolve the calcium phosphate, filtered, washed with water, and dried to obtain toner particles having a weight average particle size of 6.5 μm. I got

100 parts of the toner particles and a primary particle size of 8n
m of silica is treated with hexamethyldisilazane on its surface, and 1.2 parts of hydrophobic silica fine powder having a BET value of 250 m ² / g and 2 parts of charged particles after the treatment are mixed with a Henschel mixer (Mitsui Miike Kakoki Co., Ltd.) And polymerized toner (1) was prepared. The average circularity of the obtained toner is 0.983, and the intensity of magnetization in a magnetic field of 79.6 kA / m is 28 Am ^2.
/ Kg.

In this example, zinc oxide was used as the charged particles. The conductive fine powder made of zinc oxide used here was obtained by subjecting particles obtained by granulating primary particles of zinc oxide having a primary particle diameter of 0.1 to 0.3 μm by pressure to air classification, and a volume average. Fine particles (resistance: 10 ⁷ Ω · cm, transmittance: 35%) having a particle diameter of 1.5 μm and a particle size distribution of 0.5 vol.
This zinc oxide fine powder was 3,000 with a scanning electron microscope.
Observation at 2 × and 30,000 × revealed that the particles consisted of primary particles of zinc oxide of 0.1 to 0.3 μm and aggregates of 1 to 4 μm.

Using the image carrier and the polymerized toner (1) produced by the above procedure, an electronic roller having the configuration shown in FIG. 3 using an elastic roller charger for charging the image carrier via conductive fine powder. The evaluation was performed using a photographic device. Table 1 shows the results. The process speed at this time was 400 mm /
s, relative speed between photoconductor and elastic roller is 200% in reverse direction
And

(Calculation of silicon atom content of surface layer) A sample was placed on a silicon wafer under the same conditions as the surface layers of the negatively charged a-Si photoconductors (A1) to (A4) and (A) to (E). Was prepared, the relative value of silicon atoms and carbon atoms was measured using ESCA, and the ratio was calculated to obtain the silicon atom content (the ratio of silicon atoms to the total amount of silicon atoms and carbon).

(Charging Ability of Charging Unit)
Endurance of 10,000 passes. At this time, a constant voltage was applied to the charger, and the dark portion potential at the developing device position was measured for every 10,000 sheets, and the change in the dark portion potential due to durability was evaluated. Further, the developing bias was adjusted so that the dark area potential image was developed at the halftone density, a solid halftone image was output, and the distribution of the image density was visually evaluated. . A: No change in dark area potential was observed within the measurement error, and the halftone image was uniform. B: In the latter half of the endurance, a decrease in the dark portion potential is observed, and a slight density unevenness is observed in the halftone image. C: Dark portion potential gradually decreases during durability, and density unevenness is observed in a halftone image.

(Ejection Efficiency from Charger) At the same time as the evaluation of the chargeability of the charger, fog in a solid white portion after solid black was measured for every 10,000 sheets. At this time, the toner on the drum is peeled off with an adhesive tape to measure the density, and the density difference (density before charging—density after charging) before charging is determined from the tape peeling density before entering the charger and after passing through the charger. The ratio with respect to the concentration was defined as the discharge efficiency, and the following criteria were set and evaluated in three steps. A: Discharge efficiency of 50% or more B: Discharge efficiency of 30% or more and less than 50% C: Discharge efficiency of less than 30% (charge amount of toner discharged from the charger) Charge amount manufactured by Hosokawa Micron Corporation (hereinafter also referred to as tribo)
Measuring instrument "E-SPARTANALYZERMODEL
The charge amount distribution was measured using "ST-II". For convenience, the average charge amount was used as an index of the charge amount distribution, and the evaluation was made in three stages by setting the following criteria. FIG. 6 shows an example of the measurement result. The solid line corresponds to the measurement result of rank A, and the broken line corresponds to the measurement result of rank C. A: The average charge amount is sufficiently negative. B: The average charge amount is slightly negative. C: The average charge amount is almost 0.

(Fog) The evaluation of the charging ability of the above-mentioned charger and the evaluation of the discharge efficiency are performed, and at the same time, the TES manufactured by Canon is evaluated every 10,000 sheets.
TSHETNA-7 (A) (Part number FY9-90
60A-010), the reflection density of a white background portion was measured with a reflection densitometer (RD914 manufactured by Macbeth), and the following standard was set to evaluate the ground fog level in three steps. A: No change in reflection density was observed within the measurement error, and the ground fogging level was good. B: Increase in reflection density was observed in the latter half of endurance, and slight ground fog was observed. C: Reflection density gradually increased during endurance. The thickness of the surface layer before and after the endurance was measured with an interference type thickness meter, and the amount of abrasion was measured. Then, the following criteria were set and evaluated in three stages. A: The amount of wear is not detected within the measurement error, and is very good. B: Worn but slightly, good. C: The amount of wear is large.

Comparative Example 1 A 30 mm diameter and 2.5 mm wall thickness was obtained using the RF plasma CVD apparatus shown in FIG.
A lower blocking layer, a photoconductive layer, and a buffer layer were laminated under the conditions shown in Example 1 on a mirror-finished cylinder as an aluminum conductive substrate. Further, a surface layer made of aC: H containing a small amount of Si is laminated thereon under the following manufacturing conditions, so that the silicon atom content of the surface layer (the ratio of silicon atoms to the total amount of silicon atoms and carbon) is reduced. Different negative charging a-Si photoconductors (F) to (I) were produced. The RF frequency used was 13.56 MHz.

<Production Conditions of Photoconductor> Surface layer SiH ₄ : (F) 0 ml / min (normal) (G) 0.1 ml / min (normal) (H) 9.0 ml / min (normal) (I) 15 0.0 ml / min (normal) CH ₄ : 100 ml / min (normal) Power: 1500 W Internal pressure: 67 Pa Base temperature: 50 ° C. Film thickness: 0.3 μm The photoconductors (F) to (I) thus obtained and the polymerized toner ( 1) was evaluated in the same manner as in Example 1. Table 1 shows the results.

[0180]

[Table 1]

From the results of Example 1 and Comparative Example 1, it was found that when the silicon atom content of the surface layer was 0.2 atomic% or more, the discharge toner was negatively charged and the fog was not deteriorated. . Further, it is found that since the discharge efficiency can be maintained high by setting the content to 20 atomic% or less, the charging ability of the charger due to toner mixing does not decrease, and at the same time, the life of the charger can be ensured. Furthermore, it has been found that a lower silicon atom content is more advantageous with respect to wear. In the comprehensive evaluation, each item was judged comprehensively, and A was very good, B was good, and C was equal to or less than the conventional value.

[Embodiment 2] In the same procedure as in Embodiment 1, a-
A Si photoreceptor (B) was produced. Next, the polymerized toner (1)
Spherical toners (A) to (E) having different average circularities were produced in the same manner as in (1). A-Si thus obtained
The photoconductor (B) and the spherical toners (A) to (E) were evaluated in the same manner as in Example 1. Table 2 shows the results.

[Comparative Example 2] a-
A Si photoreceptor (B) was produced. Next, the polymerized toner (1)
In the same manner as in the above, a toner (F) was produced. The thus obtained a-Si photoreceptor (B) and toner (F) were evaluated in the same manner as in Example 1. Table 2 shows the results.

[0184]

[Table 2]

From the results of Example 2 and Comparative Example 2, since the high discharge efficiency can be maintained by setting the sphericity of the polymerized toner to 0.950 or more, the charging ability of the charger due to toner mixing does not decrease. At the same time, it was found that the life of the charger could be ensured. It has also been found that higher sphericity is more advantageous in terms of negative discharge toner tribo. In the comprehensive evaluation, each item was judged comprehensively, and A was very good, B was good, and C was equal to or less than the conventional value.

Example 3 An a-Si photosensitive member for negative charging (C) was manufactured in the same procedure as in Example 1. Next, a pulverized toner was prepared in the following procedure.・ Styrene / n-butyl acrylate copolymer (mass ratio 80/20) 100 parts by mass ・ 2 parts by mass of unsaturated polyester resin ・ 3 parts by mass of saturated polyester resin ・ Negative charge control agent (monoazo dye-based Fe compound) 1 part by mass ・ Surface-treated hydrophobized magnetic substance 90 parts by mass ・ Ester wax (maximum endothermic peak in DSC: 72 ° C.) 5 parts by mass The above materials are mixed by a blender and melted by a biaxial extruder heated to 110 ° C. The kneaded and cooled kneaded material is coarsely pulverized by a hammer mill, the coarsely pulverized material is finely pulverized by a jet mill, and then subjected to mechanical spheronization treatment. 9 μm black particles were obtained.
100 parts of the black particles are treated with hexamethyldisilazane, and then treated with silicone oil.
0.9 parts of hydrophobic silica fine powder having a value of 180 m ² / g and 2 parts of zinc oxide fine powder were mixed with a Henschel mixer (Mitsui Miike Kakoki Co., Ltd.), and pulverized toners having different average circularities ( A) and (B) were prepared. The magnetization strength of the obtained toner in a magnetic field of 79.6 kA / m is 28 Am ² / m.
kg.

The thus obtained a-Si photosensitive member (C) and pulverized toners (A) and (B) were evaluated in the same manner as in Example 1. Table 3 shows the results.

[Comparative Example 3] a-
A Si photoreceptor (C) was produced. Next, pulverized toners (C) having different average circularities were produced in the same manner as in Example 3 except that the mechanical sphering treatment was not performed. The a-Si photoconductor (C) and the pulverized toner (C) thus obtained were evaluated in the same manner as in Example 1. Table 3 shows the results.

[0189]

[Table 3]

From the results of Example 3 and Comparative Example 3, it is possible to maintain a high discharge efficiency by setting the sphericity to 0.950 or more even in the pulverized toner. It was found that the life of the charger could be ensured at the same time. Further, it was found that the higher the sphericity, the more advantageous the discharge toner tribo is in terms of negative. In the comprehensive evaluation, each item was judged comprehensively, and A was very good, B was good, and C was equal to or less than the conventional value.

[Embodiment 4] VHF plasma C shown in FIG.
A charge injection blocking layer, a photoconductive layer, a buffer layer, and a surface layer are laminated under the following conditions on a mirror-finished aluminum cylinder using an apparatus for manufacturing an a-Si photoreceptor by a VD method. The a-Si photoconductors (J1) to (J4) and (J) to (L) were obtained. The VHF frequency is 105
MHz was used.

[0192] <production conditions of the photoconductive> lower blocking layer _{· SiH 4: 200ml / min (} normal) · H 2: 400ml / min (normal) · NO: 10ml / min (normal) · PH 3: 2000ppm (SiH 4・ Power: 1200 W ・ Discharge space pressure: 0.8 Pa ・ Substrate temperature: 250 ° C. ・ Film thickness: 2 μm photoconductive layer・ SiH ₄ : 200 ml / min (normal) ・ H ₂ : 400 ml / min (normal)・ Power: 1200 W ・ Discharge space pressure: 0.8 Pa ・ Substrate temperature: 250 ° C. ・ Film thickness: 30 μm buffer layer・ SiH ₄ : 20 ml / min (normal) ・ CH ₄ : 50 ml / min (normal) ・ Power: 1200 W ・ Discharge space pressure: 0.8 Pa ・ Base temperature: 25 ° C. · thickness: 0.3 [mu] m surface layer _{· SiH 4: (J1) 0.07ml} / min (normal) (J2) 0.1ml / min (normal) (J3) 0.25ml / min (normal) (J4) 0.35ml / min (normal) (J ) 0.5ml / min (normal) (K) 2.0ml / min (normal) (L) 4.0ml / min (normal) · CH 4: 50ml / min (normal Power: 1500 W Pressure in discharge space: 0.5 Pa Base temperature: 100 ° C. Film thickness: 0.5 μm Polymerized toner (2) was prepared by the following procedure. First, a weight average particle size of 6.4 μm was obtained in the same manner as in the polymerization toner (1).
Was obtained. 100 parts of this toner particle and silica having a primary particle size of 8 nm are treated with hexamethyldisilazane on the surface, then treated with silicone oil, and BET after the treatment is treated.
1.2 parts of a hydrophobic silica fine powder having a value of 150 m ² / g and 2 parts of a conductive fine powder made of zinc oxide were mixed with a Henschel mixer (Mitsui Miike Kakoki Co., Ltd.), and polymerized toner (2 ) Was prepared. The average circularity of the obtained toner was 0.983, and the magnetization intensity in a magnetic field of 79.6 kA / m was 28 Am ² / kg.

The thus obtained photosensitive members (J1) to (J1)
4) and (J) to (L) and the polymerized toner (2)
Evaluation was performed in the same manner as in Example 1. Table 4 shows the results.

[Comparative Example 4] VHF plasma C shown in FIG.
A lower blocking layer, a photoconductive layer, and a mirror-finished cylinder as a conductive substrate made of aluminum having a diameter of 30 mm and a thickness of 2.5 mm using a VD apparatus under the conditions shown in Example 4.
A buffer layer was laminated. Further, a surface layer made of aC: H containing a small amount of Si is laminated thereon under the following manufacturing conditions, so that the silicon atom content of the surface layer (the ratio of silicon atoms to the total amount of silicon atoms and carbon) is reduced. Different negative charging a-Si photoconductors (M) and (N) were prepared.
The VHF frequency used was 105 MHz.

<Photoconductor Production Conditions> Surface layer SiH ₄ : (M) 0.03 ml / min (normal) (N) 4.5 ml / min (normal) CH ₄ : 50 ml / min (normal) Power: 1500 W Discharge Space pressure: 0.5 Pa Substrate temperature: 100 ° C. Film thickness: 0.5 μm The photoconductors (M) and (N) thus obtained and the polymerized toner (2) were evaluated in the same manner as in Example 1. Table 4 shows the results.

[0196]

[Table 4]

From the results of Example 4 and Comparative Example 4, it was found that when the silicon atom content of the surface layer was 0.2 atomic% or more, the discharge toner was negatively charged and the fog was not deteriorated. . Further, it is found that since the discharge efficiency can be maintained high by setting the content to 20 atomic% or less, the charging ability of the charger due to toner mixing does not decrease, and at the same time, the life of the charger can be ensured. Furthermore, it has been found that a lower silicon atom content is more advantageous with respect to wear. In the comprehensive evaluation, each item was judged comprehensively, and A was very good, B was good, and C was equal to or less than the conventional value.

It has been found that the same effects can be obtained in the present invention by using an a-Si photosensitive member produced by VHF. It was also found that a very good high-quality image can be obtained by using the polymerized toner as the toner.

[0199]

As described above, according to the present invention, in an electrophotographic method and apparatus using an a-Si photosensitive member as an image carrier, a conductive substrate and at least hydrogen and A photoconductive layer composed of a non-single-crystal material containing any one of halogens and containing silicon atoms as a host; and containing at least one of hydrogen and halogen and containing carbon atoms as a host and containing at least 0.2 at.
An image carrier having a surface layer composed of a non-single-crystal material containing at most atomic%, containing at least toner particles containing a binder resin and a magnetic material, and inorganic fine powder, and having an average circularity of 0.1%. 950 or more, wherein the magnetic toner has a saturation magnetization of 10 A at 79.6 kA / m.
a toner having a particle size of not less than m ² / kg and not more than 50 Am ² / kg, comprising charged particles mainly composed of conductive fine powder having a particle size of 0.1 μm to 10 μm, and a surface having conductivity and elasticity; The surface of the image carrier is supported by the charged particles, and the surface of the image carrier is negatively charged by using the charged particle carrier that comes into contact with the image carrier via the charged particles to form a latent image by an IAE method. The electrophotographic method and apparatus have made it possible to achieve an extremely good toner recycling process without a cleaning step between transfer and charging.

As a result, the amount of waste discharged over the lifetime of the electrophotographic apparatus is greatly reduced, no image deletion or image unevenness occurs in various environments, and extremely clear images can be stabilized for a long time. An electrophotographic apparatus and an electrophotographic method obtained by the above method can be provided.

Further, it is possible to provide an electrophotographic apparatus and an electrophotographic method capable of stably obtaining high-quality images for a long period of time with a long service life of the charging member and a minimum maintenance cost.

Further, the a-Si photosensitive member is uniformly charged,
It is possible to provide an electrophotographic apparatus and an electrophotographic method capable of obtaining a clear image with no unevenness, high contrast, high resolution, and low fog.

Further, in the present invention, between the photoconductive layer and the surface layer of the image bearing member, at least one of hydrogen and halogen is contained, mainly composed of silicon, and at least one of carbon, oxygen and nitrogen. Having a buffer layer made of a non-single-crystal material further containing atoms further improves the adhesion between the surface layer and the photoconductive layer, and further reduces the influence of interference due to light reflection at the interface. It is a target.

Further, according to the present invention, the surface layer has a thickness of 50 to 45.
By a plasma CVD method using a high frequency of 0 MHz,
When formed by deposition film formation by decomposing at least a hydrocarbon-based gas, a surface layer is formed under lower pressure conditions, which is more effective in suppressing deterioration of surface layer characteristics such as surface protection and light transmission. More effective.

Further, in the present invention, the image carrier is charged via the charged particles while the surface of the charged particle carrier carrying the charged particles and the surface of the image carrier are moving with a relative speed difference. When the image carrier is charged by contact with the surface, it is more effective in terms of obtaining high contact between the charged particles and the image carrier, and the surface of the charged particle carrier and the surface of the image carrier move in opposite directions to each other. It is even more effective to charge the image carrier while charging.

Further, in the present invention, if the charged particle carrier is formed of an elastic body having a porous material surface, it becomes possible to carry sufficient charged particles on the charged particle carrier.
It is even more effective in increasing the contact between the charged particles and the image carrier.

Further, in the present invention, if the charged particle carrier is a roller member having an Asker C hardness of 50 degrees or less, more preferably 25 degrees or more and 50 degrees or less, the shape stability of the charged particle carrier and the charged particles Since the ability to follow microscopic irregularities on the surface of the carrier is obtained, it is even more effective in enhancing the contact with the image carrier.

Further, in the present invention, when the charged particle carrier is a roller member having a volume resistivity of 1 × 10 ³ Ω · cm or more and 1 × 10 ⁸ Ω · cm or less, the charging characteristics and the leak resistance of the image carrier are improved. Is more effective in improving the charging characteristics for the image carrier.

Further, in the present invention, the resistance of the conductive fine powder is 1 × 10 ⁹ Ω · cm or less, more preferably 1 × 10 ⁻¹ Ω · cm.
It is more effective to improve the charge promotion for the image bearing member when it is not less than cm and not more than 1 × 10 ⁹ Ωcm.

Further, in the present invention, if the conductive fine powder is configured to adhere to the surface of the toner, excessive charging of the toner is prevented, and the effect of preventing the deterioration of the developing property due to the excessive charging of the toner is further improved. It is a target.

Further, in the present invention, when the inorganic fine powder is subjected to the hydrophobic treatment, the change in the characteristics of the inorganic fine powder due to environmental fluctuation can be further suppressed, and the charging property, developing property, transfer property, Regarding the image quality of the formed image,
It is more effective in preventing a change in characteristics due to an environmental change.

Further, in the present invention, the conductive fine powder adhering to the surface of the toner adheres to the image carrier in the developing step, and remains on the image carrier after the transfer step to carry the charged particles. If it is configured to reach the body, it becomes possible for the developing means to also serve as a means for supplying charged particles to the charged particle carrier,
It is even more effective from the viewpoint of downsizing of the device and improvement of maintainability.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an example of an electrophotographic photosensitive member used in an electrophotographic apparatus of the present invention.

FIG. 2 is a schematic sectional view showing another example of the electrophotographic photosensitive member used in the electrophotographic apparatus of the present invention.

FIG. 3 is a schematic sectional view illustrating an example of an electrophotographic apparatus used in the present invention.

FIG. 4 is a schematic cross-sectional view showing one example of a deposition apparatus for forming the electrophotographic photosensitive member of the present invention.

FIG. 5 is a schematic cross-sectional view showing one example of a deposition apparatus for forming the electrophotographic photosensitive member of the present invention.

FIG. 6 is a diagram illustrating an example of a result of measuring a charge amount distribution of a toner.

DESCRIPTION OF SYMBOLS 101 Conductive substrate 102 Lower blocking layer (charge injection blocking layer) 103 Photoconductive layer 104 Buffer layer 105 Surface layer 106 Charge generation layer 107 Charge transport layer 201 Electrophotographic image carrier (photoconductor) 202 Contact charging Member (charged particle carrier) 203 Laser beam 204 Developing device (developing device) 205 Toner 206 Transfer roller (transfer device) 207 Transfer material (recording medium) 208 Inverted toner 209 Fixing device 2100, 3100 Stacking device 2110, 3110 Reaction container 2111 , 3111 cathode electrode 2112, 3112 conductive substrate 2113, 3113 conductive substrate heating heater 2114 source gas introduction pipe 2115, 3115 high frequency matching box 2116 gas supply pipe 2117 leak valve 2118 main valve 2119 vacuum 2120 High frequency power supply 2121 Insulating material 2123 Conductive pedestal 2200 Source gas supply device 2211 to 2216 Mass flow controller 2221 to 2226 Source gas cylinder 2231 to 2236 Valve 2224 to 2246 Inflow valve 2251 to 2256 Outflow valve 2260 Auxiliary valve 2261 to 2266 Pressure regulator 3120 Rotating motor 3121 Exhaust port 3130 Discharge space

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03G 9/08 374 G03G 9/08 374 9/083 15/02 101 15/02 101 103 103 9/08 101 15/08 507 15/08 507B (72) Inventor Junichiro Hashizume 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Masaharu Miura 3-30-2 Shimomaruko, Ota-ku, Tokyo Kyano 2H005 AA01 AA02 AA08 AA15 EA02 2H068 DA04 DA05 DA24 DA54 DA55 DA56 DA57 EA24 FC03 2H077 AA37 AC11 AC16 AD02 AD06 GA04 2H200 FA14 GA15 GA23 GA33 GA44 GB11 GB37 HA02 HA21 HA29 HB12 HB47B JAB JA28 MA08 MB01 MB04 MB06 MC01 MC02 NA02 PA11

Claims (30)

[Claims] A charging step of charging a surface of a rotating image carrier; a latent image forming step of forming an electrostatic latent image on a charged surface of the image carrier; and attaching toner to the surface of the image carrier. A developing step of developing the electrostatic latent image as a toner image, and a transfer step of transferring the toner image to a recording medium, wherein the image carrier has a conductive base, A photoconductive layer formed of a non-single-crystal material on a conductive substrate and containing at least one of hydrogen and halogen and containing silicon atoms as a host; and a photoconductive layer containing at least one of hydrogen and halogen and containing carbon atoms as a host and containing at least silicon atoms And a surface layer composed of a non-single-crystal material containing Si / (Si + C) in an amount of 0.2 atomic% or more and 20 atomic% or less, wherein the toner comprises at least a binder resin and a magnetic material. And nothing A magnetic toner having an average circularity of 0.950 or more, wherein the saturation magnetization of the magnetic toner at 79.6 kA / m is 10 Am ² /
kg or more and 50 Am ² / kg or less, and the charging step includes charged particles mainly composed of conductive fine powder having a particle size of 0.1 μm to 10 μm, and a surface having conductivity and elasticity. The charged particles are supported, and the surface of the image carrier is negatively charged by using a charged particle carrier contacting the image carrier via the charged particles, and the latent image forming step includes:
An electrophotographic method comprising: a latent image forming step of forming an electrostatic latent image by exposing an image portion to attenuate a potential to form an electrostatic latent image, wherein there is no cleaning step between transfer and charging. 2. The method according to claim 1, wherein the surface of the image carrier includes at least one of hydrogen and halogen, and is mainly composed of silicon and at least one of carbon, oxygen, and nitrogen. 2. The electrophotographic method according to claim 1, further comprising a buffer layer made of a non-single-crystal material further containing atoms. 3. The method according to claim 1, wherein the surface layer is formed by depositing a film by decomposing at least a hydrocarbon gas by a plasma CVD method using a high frequency of 50 to 450 MHz. 3. The electrophotographic method according to 2. 4. The charging step includes charging the charged particles while the surface of the charged particle carrier carrying the charged particles and the surface of the image carrier are moving with a relative speed difference. The electrophotographic method according to any one of claims 1 to 3, wherein the image carrier is charged by contacting the image carrier via the image carrier. 5. The electrophotographic apparatus according to claim 4, wherein in the charging step, the image carrier is charged while the surface of the charged particle carrier and the surface of the image carrier move in directions opposite to each other. Method. 6. The electrophotographic method according to claim 1, wherein, in the charging step, the charged particle carrier is formed of an elastic body having a porous body surface. 7. The electrophotographic method according to claim 1, wherein the charged particle carrier is a roller member having an Asker C hardness of 50 degrees or less. 8. The electrophotographic method according to claim 1, wherein the charged particle carrier is a roller member having an Asker C hardness of 25 to 50 degrees. 9. The roller according to claim 1, wherein the charged particle carrier is a roller member having a volume resistivity of 1 × 10 ³ Ω · cm or more and 1 × 10 ⁸ Ω · cm or less. The electrophotographic method according to claim 1. 10. The resistance of the conductive fine powder is 1 × 10 ⁹
The electrophotographic method according to any one of claims 1 to 9, wherein the resistance is Ω · cm or less. 11. The resistance of the conductive fine powder is 1 × 10 ⁻¹
The electrophotographic method according to any one of claims 1 to ^{9, wherein the} resistivity is not less than Ω · cm and not more than 1 × 10 ⁹ Ω · cm. 12. The electrophotographic method according to claim 1, wherein the toner has a conductive fine powder on a surface thereof. 13. The electrophotographic method according to claim 1, wherein the toner has an inorganic fine powder that has been subjected to a hydrophobic treatment. 14. The electrophotographic method according to claim 1, wherein the inorganic fine powder is treated with silicone oil. 15. The method according to claim 15, wherein the conductive fine powder adheres to the image carrier in the developing step, remains on the image carrier after the transfer step, and reaches the charged particle carrier. The electrophotographic method according to claim 12, wherein: 16. A rotating image carrier, charging means for charging the surface of the image carrier, latent image forming means for forming an electrostatic latent image on a charged surface of the image carrier, and the image carrier In an electrophotographic apparatus including a developing unit that develops the electrostatic latent image as a toner image by attaching toner to a surface thereof, and a transfer unit that transfers the toner image to a recording medium, the image carrier is A conductive substrate, a photoconductive layer formed on the conductive substrate of a non-single-crystal material containing at least one of hydrogen and halogen and containing silicon atoms as a host, and a carbon containing at least one of hydrogen and halogen. A surface layer composed of a non-single-crystal material containing at least 0.2 atomic% and not more than 20 atomic% of silicon atoms in Si / (Si + C) based on the atoms, and the toner comprises at least a binder resin and Contains magnetic material A toner having an average circularity of 0.950 or more and a saturation magnetization at 79.6 kA / m of not less than 10 Am ² / kg and not more than 50 Am ² / kg. And
The charging unit includes charged particles mainly composed of conductive fine powder having a particle size of 0.1 μm to 10 μm, and a surface having conductivity and elasticity. A charged particle carrier that contacts the image carrier through the particles, the surface of the image carrier is negatively charged, and the latent image forming unit exposes the image area to attenuate the potential. 1. An electrophotographic apparatus comprising: a latent image forming unit that forms an electrostatic latent image by using a cleaning unit between transfer and charging. 17. A method according to claim 1, wherein the photoconductive layer and the surface layer of the image bearing member contain at least one of hydrogen and halogen, are mainly composed of silicon, and are at least one selected from carbon, oxygen and nitrogen. 17. The electrophotographic apparatus according to claim 16, further comprising a buffer layer made of a non-single-crystal material further containing atoms. 18. The method according to claim 16, wherein the surface layer is formed by depositing a film by decomposing at least a hydrocarbon-based gas by a plasma CVD method using a high frequency of 50 to 450 MHz. 18. The electrophotographic apparatus according to 17. 19. The charging unit according to claim 1, wherein the surface of the charged particle carrier supporting the charged particles and the surface of the image carrier are moving with a relative speed difference. The electrophotographic apparatus according to any one of claims 16 to 18, wherein the image carrier is charged by contacting the image carrier via the image carrier. 20. The electronic device according to claim 19, wherein the charging unit charges the image carrier while the surface of the charged particle carrier and the surface of the image carrier move in directions opposite to each other. Photo equipment. 21. The electrophotographic apparatus according to claim 16, wherein in the charging unit, the charged particle carrier is formed of an elastic body having a porous body surface. 22. The electrophotographic apparatus according to claim 16, wherein the charged particle carrier is a roller member having an Asker C hardness of 50 degrees or less. 23. The electrophotographic apparatus according to claim 16, wherein the charged particle carrier is a roller member having an Asker C hardness of 25 degrees or more and 50 degrees or less. 24. The roller according to claim 16, wherein the charged particle carrier is a roller member having a volume resistivity of 1 × 10 ³ Ω · cm or more and 1 × 10 ⁸ Ω · cm or less. An electrophotographic apparatus according to the item. 25. The conductive fine powder has a resistance of 1 × 10 ^9.
3. The resistance according to claim 1, wherein the resistance is Ω · cm or less.
5. The electrophotographic apparatus according to claim 4. 26. The resistance of the conductive fine powder is 1 × 10 ⁻¹
25. The electrophotographic apparatus according to any one of claims 16 to 24, wherein the resistance is not less than Ω · cm and not more than 1 × 10 ⁹ Ω · cm. 27. The electrophotographic apparatus according to claim 16, wherein said toner has conductive fine powder on a surface thereof. 28. The toner according to claim 16, wherein the toner comprises an inorganic fine powder that has been subjected to a hydrophobic treatment.
The electrophotographic apparatus according to any one of the above. 29. An electrophotographic apparatus according to claim 16, wherein said inorganic fine powder is treated with silicone oil. 30. The method according to claim 30, wherein the conductive fine powder adheres to the image carrier by the developing means, remains on the image carrier after the toner image is transferred, and reaches the charged particle carrier. The electrophotographic apparatus according to claim 27, wherein: